SECTION 1. SHORT TITLE.

    This Act may be cited as the ``Complete America's Great Trails 
Act''.

SEC. 2. NATIONAL SCENIC TRAIL CONSERVATION CREDIT.

    (a) In General.--Subpart B of part IV of subchapter A of chapter 1 
of the Internal Revenue Code of 1986 is amended by adding at the end 
the following new section:

``SEC. 30E. NATIONAL SCENIC TRAIL CONSERVATION CREDIT.

    ``(a) Allowance of Credit.--There shall be allowed as a credit 
against the tax imposed by this chapter for the taxable year an amount 
equal to the fair market value of any National Scenic Trail 
conservation contribution of the taxpayer for the taxable year.
    ``(b) National Scenic Trail Conservation Contribution.--For 
purposes of this section--
            ``(1) In general.--The term `National Scenic Trail 
        conservation contribution' means any qualified conservation 
        contribution--
                    ``(A) to the extent the qualified real property 
                interest with respect to such contribution includes a 
                National Scenic Trail (or portion thereof) and its 
                trail corridor, and
                    ``(B) with respect to which the taxpayer makes an 
                election under this section.
            ``(2) National scenic trail.--The term `National Scenic 
        Trail' means any trail authorized and designated under section 
        5 of the National Trails System Act (16 U.S.C. 1244), but only 
        if such trail is at least 200 miles in length.
            ``(3) Trail corridor.--The term `trail corridor' means so 
        much of the corridor of a trail as is--
                    ``(A) not less than--
                            ``(i) 150 feet wide on each side of such 
                        trail, or
                            ``(ii) in the case of an interest in real 
                        property of the taxpayer which includes less 
                        than 150 feet on either side of such trail, the 
                        entire distance with respect to such interest 
                        on such side, and
                    ``(B) not greater than 2,640 feet wide.
            ``(4) Qualified conservation contribution; qualified real 
        property interest.--The terms `qualified conservation 
        contribution' and `qualified real property interest' have the 
        respective meanings given such terms by section 170(h), except 
        that a qualified real property interest shall include the 
        entire interest of the taxpayer in real property.
    ``(c) Special Rules.--
            ``(1) Fair market value.--Fair market value of any National 
        Scenic Trail conservation contribution shall be determined 
        under rules similar to the valuation rules under Treasury 
        Regulations under section 170, except that in any case, to the 
        extent practicable, fair market value shall be determined by 
        reference to the highest and best use of the real property with 
        respect to such contribution.
            ``(2) Election irrevocable.--An election under this section 
        may not be revoked.
            ``(3) Denial of double benefit.--No deduction shall be 
        allowed under this chapter with respect to any qualified 
        conservation contribution with respect to which an election is 
        made under this section.
    ``(d) Limitation Based on Amount of Tax; Carryforward of Unused 
Credit.--
            ``(1) Limitation.--The credit allowed under subsection (a) 
        for any taxable year shall not exceed the sum of--
                    ``(A) the taxpayer's regular tax liability for the 
                taxable year reduced by the sum of the credits 
                allowable under subpart A and sections 27, 30, 30B, 
                30C, and 30D, plus
                    ``(B) the tax imposed by section 55.
            ``(2) Carryforward.--
                    ``(A) In general.--If the credit allowable under 
                subsection (a) exceeds the limitation imposed by 
                paragraph (1) for any taxable year, such excess shall 
                be carried to the succeeding taxable year and added to 
                the credit allowable under subsection (a) for such 
                succeeding taxable year.
                    ``(B) Limitation.--No credit may be carried forward 
                under this subsection to any taxable year following the 
                tenth taxable year after the taxable year in which the 
                credit arose. For purposes of the preceding sentence, 
                credits shall be treated as used on a first-in first-
                out basis.''.
    (b) Continued Use Not Inconsistent With Conservation Purposes.--A 
contribution of an interest in real property shall not fail to be 
treated as a National Scenic Trail conservation contribution (as 
defined in section 30E(b) of the Internal Revenue Code of 1986) solely 
by reason of continued use of the real property, such as for 
recreational or agricultural use (including motor vehicle use related 
thereto), if, under the circumstances, such use does not impair 
significant conservation interests and is not inconsistent with the 
purposes of the National Trails System Act (16 U.S.C. 1241, et seq.).
    (c) Study Regarding Efficacy of National Scenic Trail Conservation 
Credit.--
            (1) In general.--The Secretary of the Interior shall, in 
        consultation with the Secretary of the Treasury, study--
                    (A) the efficacy of the National Scenic Trail 
                conservation credit under section 30E of the Internal 
                Revenue Code of 1986 in completing, extending, and 
                increasing the number of National Scenic Trails (as 
                defined in section 30E(b) of such Code), and
                    (B) the feasibility and estimated costs and 
                benefits of--
                            (i) making such credit refundable (in whole 
                        or in part), and
                            (ii) allowing transfer of such credit.
            (2) Report.--Not later than 4 years after the date of the 
        enactment of this Act, the Secretary of the Interior shall 
        submit a report to Congress on the results of the study 
        conducted under this subsection.
    (d) Conforming Amendment.--The table of sections for subpart B of 
part IV of subchapter A of chapter 1 of such Code is amended by adding 
at the end the following new item:

``30E. National Scenic Trail conservation credit.''.
    (e) Effective Date.--The amendments made by this section shall 
apply to contributions made after the date of the enactment of this 
Act.
Complete America's Great Trails Act - Amends the Internal Revenue Code to allow a tax credit for the fair market value of any National Scenic Trail conservation contribution. Requires the Secretary of the Interior to study and report to Congress on the efficacy of such tax credit in completing, extending, and increasing the number of National Scenic Trails.
To amend the Internal Revenue Code of 1986 to allow a credit against income tax for qualified conservation contributions which include National Scenic Trails.