This cause is before the Court on petition for review of a decision of a district court of appeal reported as Nalven v. Division of Administration, 409 So.2d 166 (Fla.2d DCA 1982). The district court of appeal certified that its decision passed upon a question of great public importance. The Department of Transportation petitioned for discretionary review of the decision both on the jurisdictional ground of the certified question and on the ground of direct and express conflict of decisions. We accept jurisdiction based on the certified question. Art. V, § 3(b)(4), Fla. Const.
In essence this case presents a question of the admissibility of testimony ostensibly based upon expert opinion. But the eviden-tiary question turns on the resolution of questions arising from the use of market value as the basic indicator of “full compensation” for property taken by eminent domain as required by the Florida Constitution. Rejecting the Department of Transportation’s argument that the state should not have to compensate for value attributable to anticipation of the project for which the property is being taken, the district court held that a landowner is entitled to receive the fair market value of the property at the time of the taking. For the reasons that follow we approve the decision of the district court.
On February 14, 1977, the Department of Transportation initiated proceedings for condemnation of several parcels of land needed for the construction of a portion of Interstate Highway 75 in Manatee County. Among the defendant landowners were the respondents Robert and Lionel Nalven, who owned a tract of approximately one thousand acres, of which 91.5 acres were condemned for the highway right-of-way. By the time the case went to trial, the only remaining matter of dispute between respondents and the state was the valuation of, and compensation to be paid for, the 91.5 acres to be taken by the state.
At trial each side presented the testimony of an appraisal expert. Both experts testified that the best way to determine the market value of unimproved land is to gather and examine information on the sales prices of similar land in the same area. They testified further that the similarities and differences in various characteristics of the parcels studied should then be analyzed in order to find the recent land sales that are most “comparable.” The characteristics studied are those which relate most directly to market value, such as size, location, topography, road access, drainage, waterfront access, and proximity to beneficial or obnoxious facilities or projects. These “comparable sales” are then expected to reveal market values that can be used to approximate the market value of the land being appraised.
The landowners’ expert testified that of the fourteen sales in Manatee and Sarasota Counties that he considered, three related to parcels that were most comparable to the land being taken. The three comparable sales considered by the landowners’ expert were: (1) a 1973 sale of the parcel to be appraised (i.e., the owners’ thousand-acre tract of which the 91.5 acres being condemned were a part), which yielded $2,100 per acre; (2) a 1973 sale of a nearby parcel referred to as Creekwood, which sold for $2,365 per acre; and (3) a later sale of a parcel in Sarasota County, referred to as The Meadows, for $3,500 per acre. The expert testified that after making further adjustments based on the passage of time and refinements based on remaining differences, he concluded that as of the date of his testimony the land being taken for the highway had a market value of $2,350 per acre resulting in an appraisal of $215,110.
The Department of Transportation’s expert testified that although the prior sale *303of respondents’ property and the sale of Creekwood were among the recent sales of comparable properties in the area, he excluded them from his analysis because the sales prices of the parcels reflected an increase in market value resulting from the expectation of the proposed highway project. He expressed the opinion, that is, that in 1973 the two parcels sold for more than they would have in the absence of any anticipation of the construction of the interstate highway. The Department’s expert appraised the land at $1,440 per acre, thus giving it a total value of $131,825. The landowners’ counsel moved to strike this testimony but the trial judge allowed it to stand. The jury returned a verdict fixing the compensation at $133,525, which reflected acceptance of the state expert’s valuation plus an allowance for fencing replacement costs. The landowners appealed.
The sales discarded from consideration by the state’s appraiser occurred in 1973. The record shows that on November 7, 1974, the Department of Transportation adopted a resolution indicating the general location proposed for Interstate 75. On February 1, 1977, the Department adopted a resolution specifying the route and identifying the particular tracts of land needed for the construction of the highway. The instant condemnation action was begun shortly thereafter. The Department argues that the sales in question were properly disregarded even though they occurred before the official acts identifying either generally or specifically the location of the highway. The Department argues that even before November 7, 1974, there was general knowledge in the marketplace concerning the location; it was openly discussed in public meetings and in documents open to public inspection. There was testimony that the 1973 sales were negotiated in light of common awareness of the proposed general location of the highway.
On appeal the district court held that the trial court had erred in refusing to strike the testimony of the Department’s expert that the two excluded sales were inappropriate to consider and his appraisal testimony based thereon. The district court explained that “any pertinent sale of land comparable to the condemned land which occurs before the date of the taking can be considered in determining value even if the sales price is enhanced by virtue of the proposed improvement.” 409 So.2d at 169. Thus the district court concluded, and correctly so, that the state’s expert went beyond his appraisal expertise and expressed to the jury an erroneous legal conclusion. The district court also concluded that since the state expert obviously influenced the jury with his erroneous theory, the judgment would be reversed for a new trial.
In reaching its decision the district court relied upon the long-standing precedent of Sunday v. Louisville & Nashville Railroad, 62 Fla. 395, 57 So. 351 (1912). There the Supreme Court of Florida reversed a condemnation award and remanded for a new trial on compensation because the trial judge had instructed the jury not to consider any enhancement in the value of the property taken caused by the proposed improvement. This Court explained that
the law does not deny to the owner any real and reasonable enhancement in the market value of the property to be appropriated by reason of “any improvement proposed.” If the property naturally, or in common with other property similarly conditioned, increases in market value in anticipation of the proposed improvement, before the appropriation, the compensation therefor is the fair actual market value at the time of the lawful appropriation.
62 Fla. at 397, 57 So. at 351 (emphasis in original). The error in Sunday was in an instruction to the jury. But the district court correctly recognized that the principle of full compensation at the time of taking also applies to render inadmissible any expert opinion testimony based on an erroneous theory of valuation. Anderson v. State Road Department, 204 So.2d 899 (Fla. 1st DCA 1967).
Although correct in its application of the law, the district court went on to *304suggest several reasons why this Court might wish to depart from the rule expressed in Sunday v. Louisville & Nashville Railroad. After setting out its concerns the district court certified its decision as having passed upon a question of great public importance. The district court framed the certified question as follows:
To what extent, if any, is a Florida property owner in a condemnation proceeding entitled to the enhancement in the value of his property caused by the anticipation of the proposed project for which the land is being condemned?
409 So.2d at 171. We answer the question by holding that a landowner in a condemnation proceeding is entitled to the fair market value of the property at the time of the taking even if it reflects the anticipation of the proposed project.
The Department of Transportation argues that its expert’s testimony was properly allowed. The Department urges that a landowner whose property is taken should be compensated on the basis of the value of the property prior to any enhancement in value caused by the anticipation of the project for which the land is being taken. The Department asks us to adopt a rule of law in effect freezing the value of the land to be taken as of the time when the state becomes committed to placing the public project in a certain area, or, expressed another way, the time when the scope of the project becomes known in the market. The “scope-of-the-project” rule, the Department says, would exclude project influence from the appraisal of value and from the determination of just compensation, thereby protecting the public from having to pay a premium for needed lands and preventing landowners from reaping windfall profits simply because the state has an absolute need for certain land. The Department cites United States v. 320.0 Acres of Land, 605 F.2d 762 (5th Cir.1979), and numerous decisions from other states in support of the wisdom of such a rule.
Attempting to clear the way for us to adopt the so-called “scope-of-the-project” rule, the Department argues that Sunday v. Louisville & Nashville Railroad is inapplicable to the problem before us because: (1) it was based on a provision of the 1885 constitution which applied only to exercises of the power of eminent domain by private individuals and corporations and (2) the provision of the 1885 constitution upon which the decision was based has been eliminated and has no counterpart in the present Florida constitution or in the statutes. Finally the Department argues that if the Sunday rule is still the law of Florida and is applicable to the facts of this case then it should be abrogated in favor of the “scope-of-the-project” rule. We shall discuss the Department’s constitutional and historical arguments first and shall then deal with its public policy arguments for a change in the law.
Article XVI, section 29 of the Florida Constitution of 1885 governed the appropriation of private property and rights of way to the use of corporations and individuals by eminent domain. It pertained to any legislatively authorized condemnation for purposes such as railroads, utilities easements, ways of necessity, drainage, and the like. It provided in part that the compensation for such takings should be ascertained “irrespective of any benefit from any improvement proposed by such corporation or individual.” 1 The Department asserts that the holding in Sunday was grounded squarely on the constitutional language and argues that since both article XVI, section 29 and the Sunday case pertained to condemnation by private corporations Sunday has no applicability to the instant *305ease. This argument is erroneous. Petitioner is correct in pointing out that article XVI, section 29 applied only to private condemnations. Daniels v. State Road Department, 170 So.2d 846 (Fla.1964).2 The Sunday decision, however, provided in essence a construction of the constitutional words, “full compensation,” and mentioned the constitutional words, “irrespective of any benefit,” etc., only to refute any suggestion that they limited or qualified the meaning of “full compensation.” Since article X, section 6, of our present constitution requires full compensation in all exercises of the eminent domain power, both public and on behalf of individuals or corporations, Sunday is still controlling authority and now applies even where the condemning authority is a state agency.3
The Department also argues that since the language “irrespective of any benefit from any improvement proposed by such corporation or individual,” was eliminated by the constitutional revision of 1968, Sunday is no longer the law of Florida. Like the assertions just discussed, this argument also assumes that the Sunday decision was compelled by the constitutional language. A careful reading of the Sunday opinion, however, reveals that the decision was rendered not because of but in spite of the quoted language.4 Far from being grounded in the constitutional language, “irrespective of any benefit,” the Sunday decision held the language inapplicable to the facts of the case, that is, inapplicable to enhancement in market value of the land taken due to anticipation of the project. The Court mentioned the constitutional language in order to explain why it did not compel the conclusion sought by the appellee, the condemnor. The “benefit” referred to in article XYI, section 29 meant not enhancement in the value of the land taken, but rather any increase in the value of land not taken, as, for example, by reason of its being adjacent to a railroad or other improvement. The quoted clause was meant to negate any intention of allowing a private condemnor to offset the value of benefits to the remainder of the condemnee’s land against the compensation paid for the property taken. See Daniels v. State Road Department, 170 So.2d 846 (Fla.1964); § 73.071(4), Florida Statutes (1981).5 Therefore, the clause, “irrespec*306tive of any benefit,” etc., was not the basis for the Sunday decision. Sunday applied the concept of “full compensation” applicable to takings by individuals and corporations under the 1885 constitution. Under article X, section 6 of the Florida Constitution of today, “full compensation” is to be paid for all property taken by condemnation, whether by a state agency or an authorized private person. Therefore, the absence of language in article X, section 6 corresponding to “irrespective of any benefit from any improvement,” does not in any way indicate that the rule of Sunday has been abrogated. As the district court correctly recognized, Sunday continues to be the law of Florida and fully applies to this case.
*30562 Fla. at 397, 57 So. at 351.
(4) When the action is by the Division of Road Operations, county, municipality, board, *306district or other public body for the condemnation of a road, canal, levee or water control facility right-of-way, the enhancement, if any, in value of the remaining adjoining property of the defendant property owner by reason of the construction or improvement made or contemplated by the petitioner, shall be offset against the damage, if any, resulting to such remaining adjoining property of the defendant property owner by reason of the construction or improvement, but such enhancement in the value shall not be offset against the value of the property appropriated, and if such enhancement in value shall exceed the damage, if any, to the remaining adjoining property there shall be no recovery over against such property owner for such excess. The present case, of course, presents no issue of remainder damages or remainder value enhancement.
We come now to the Department’s plea for a change in the law. As was stated above the Department urges upon us the “scope-of-the-project” rule. Such rule, as interpreted by the state, would admit the expert’s testimony that the questioned sales were to be discarded from consideration on the ground that they were negotiated at a time when the general location of the interstate highway through Manatee County was known in the real estate marketplace.
The “scope-of-the-project” rule was first announced in United States v. Miller, 317 U.S. 369, 63 S.Ct. 276, 87 L.Ed. 336 (1943). There the government took various lands by damming a river and flooding a valley, creating a large lake. On the shore of the lake there grew a small settlement, drawn there by the amenities offered by the lake. Among those dispossessed by the flooding project was a railroad, whose right-of-way therefore had to be relocated. When the government sought to condemn a part of the newly settled area for railroad purposes, the owners claimed the right to be compensated for the value of their lands as part of a desirable lakeside community, while the government sought to value it as what it was before the creation of the lake, uncleared brush lands. Finding that relocation of the railroad had been part of the project from its inception and that it was public knowledge that the route of it would probably be through the condemnees’ lands, the Court held they were not entitled to receive the market value of their land as enhanced by river dam project. In so holding the Court fashioned the “scope-of-theproject” rule. Thus the rule developed in what many commentators call a “supplementary taking” or “expanded project” situation. See, e.g., 4 J. Sackman, Nichols’ Law of Eminent Domain § 12.3151[3] (rev. 3d ed. 1981). Such is not the situation we deal with here.
In support of its position, the Department relies on United States v. 320.0 Acres of Land, 605 F.2d 762 (5th Cir.1979), which provided a detailed explanation of the “scope-of-the-project” rule. The Court said that the rule (1) protects the government from having to pay false, “hold-up” value attributable to the government’s special need for particular property and (2) prevents the payment of compensation for value attributable to benefits conferred on the land (together with neighboring lands) by the proposed project for which the land is being taken.
We decline to adopt the scope-of-the-project rule. The constitution of Florida and the applicable statute control. Article X, section 6(a) of the Florida Constitution, provides: “No private property shall be taken except for a public purpose and with full compensation therefor paid to each owner or secured by deposit in the registry *307of the court and available to the owner.” Section 73.071(2), Florida Statutes (1975), provides: “The amount of such compensation shall be determined as of the date of trial, or the date upon which title passes, whichever shall occur first.”
The constitutional requirement of full compensation means that the landowner must be completely paid for that which is taken, and compensated for the whole loss occasioned by the taking. Florida East Coast Railway v. Martin County, 171 So.2d 873 (Fla.), cert. denied, 382 U.S. 834, 86 S.Ct. 79,15 L.Ed.2d 78 (1965); Meyers v. City of Daytona Beach, 158 Fla. 859, 30 So.2d 354 (1947). In most cases it will be necessary and sufficient to full compensation that the award constitute the fair market value of the property. Casa Loma Springs Development Co. v. Brevard County, 93 Fla. 601, 112 So. 60 (1927); Sunday v. Louisville & Nashville Railroad.
To accept the Department’s argument that the 1973 sales were properly discarded because of awareness of the project (even though they took place prior to both the general and the specific announcements of the location of the route of Interstate 75 through Manatee County) would lead the courts of the state into inquiries for which there would be no clear lines of distinction. Before it was decided that Interstate 75 would traverse Manatee County, it had to be decided that the highway would extend into southwest Florida. Before it was decided that the highway would run through southwest Florida, a decision was made that it would enter the southern half of the Florida peninsula. Before it was decided that the highway would extend into southern Florida, there was a plan for an interstate limited access highway connecting Florida with the other states of the eastern United States, which would extend into central Florida from the north. The interstate highway system and proposals for its various routes have been under discussion for decades. Fixing the date when the scope of such a project was known in the market is a task much more easily discussed in theory than performed in deciding actual cases.
When a project such as a limited-access highway is announced and the general area through which it is to pass is known to the public, but the specific location is yet to be decided, there may well be marked increases in market values in the area due to the anticipation of the project, but these increases will result from a whole host of diverse influences and market forces. For example, once it became known that Interstate 75 was to be extended into southern Florida it could be assumed that it would be placed so as to serve the rapidly growing regions of the west coast, including Manatee and Sarasota Counties. Even this much general knowledge could have and probably did cause a general increase in land values, since good interstate highway access can make a region a more desirable place to live. Similarly, by making the Manatee-Sarasota area more accessible from the north by automobile, the highway (and anticipation thereof) probably stimulated all elements of the tourism industry, thereby also having an enhancing effect on land values generally. Thus it is very difficult to determine where to draw the line against value enhancement due to project anticipation when determining fair market value for compensation purposes.
In holding that a property owner is entitled to full compensation based on fair market value at the time of taking including increased value due to anticipation of the project, we of course do not mean to say that the state should have to pay inflated compensation based on false, “hold-up” value attributable purely to government demand for the particular parcel. It should remain open to the state to try to show through expert testimony that the valuation claimed by the landowner reflects false, “hold-up” value due purely to specific demand. But if the landowner, using established conventional appraisal methods, establishes fair market value of the land on the date of taking, the mere fact that it is greater than the value before the location of the project was announced or became *308known does not deprive the landowner of the right to full compensation based on fair market value at the time of taking.
The general rule that the special need of the condemning authority should not be allowed to enhance the value of property for purposes of determining the compensation to be paid is but a corollary of the rule that compensation should be based on fair market value. The true market value of property is not likely to increase as a result of its being specifically targeted for condemnation. Indeed, as this Court recognized in State Road Department v. Chicone, 158 So.2d 753 (Fla.1963), the more probable result is a decrease in value:
[W]hen land is definitely marked for condemnation ... it shares none of the beneficial effects which could flow from anticipation of the proposed improvement for it will not be available for private use when the project is completed. Once selected for condemnation the marketability, both sale and rental, and to some extent the use, of property is sterilized and its value, either as determined by market value or use by the owner, is decreased. This decrease no doubt is in proportion to the lapse of time between the announcement that the lands will be taken and the actual taking. It is difficult to conceive of a situation in which property will increase in value because of the prospect of condemnation. A tenant’s use of such property can only be temporary, and a purchaser would buy only an undetermined award in a condemnation suit.
158 So.2d at 754-55. The Court in Chicone held that when land specifically designated for condemnation depreciates in value after such designation but before the date of actual taking, the owner should be compensated on the basis of the market value prior to such depreciation. The decision was grounded in considerations of equity and fairness. This Court subsequently reaffirmed the principle of Chicone in Dade County v. Still, 377 So.2d 689 (Fla.1979).
The record reveals that the landowners’ tract (of which a part has been taken) and Creekwood were large parcels both of which were bisected by the construction of the north-south interstate highway. Both parcels were contiguous to existing roads which were to be connected to the limited-access highway by interchanges. When a state witness made reference to interchanges at trial, the landowners’ counsel objected and the testimony was stricken. In its brief, the Department points out that property contiguous to an interstate highway at its interchanges or access points can be expected to greatly increase in market value because of its suitability for commercial use. Although the argument is not explicitly made, the Department seems to suggest that when part of an owner’s land is taken for highway construction, but the owner is left with land adjacent to an interchange, the increase in the value of what he is left with justifies paying depressed value for the land taken. This is, of course, expressly forbidden by section 73.-071(4), Florida Statutes (1975).
The landowners’ parcel sold for $2,100 per acre in 1973. At the condemnation trial four years later the Department's expert appraised it at nearly $700 per acre less on the ground that the 1973 sale and another comparable sale reflected enhancement due to anticipation of the highway construction project. We hold that this testimony was based on an erroneous legal premise and should not have been allowed.
Consistent with Sunday v. Louisville & Nashville Railroad, we hold that if the 1973 sales of the landowners’ property and Creekwood reflected market value that had increased because of public knowledge of the probable alignment of Interstate 75 in Manatee County, such was a natural increase in market value and was not to be disregarded or discounted in determining market value at the time of the taking.
The trial court erred in refusing to strike the testimony of the Department’s appraisal witness because the testimony was based on a legal proposition which we, consistent with precedent, hold to be erroneous. The district court correctly so held in reversing the judgment. The decision of *309the district court of appeal ordering a new trial is approved.
It is so ordered.
ALDERMAN, C.J., and ADKINS and SHAW, JJ., concur.
OVERTON, J., dissents with an opinion, in which McDONALD and EHRLICH, JJ., concur.
McDONALD, J., dissents with an opinion, in which OVERTON and EHRLICH, JJ., concur.