City Charter § 2.4.5 - Sale and leasing of parks.

Without the approval of a majority of those registered electors voting in an
election held by the City and County of Denver, no park or portion of any
park belonging to the City as of December 31, 1955, shall be sold or leased
at any time, and no land acquired by the City after December 31, 1955, that
is designated a park by ordinance shall be sold or leased at any time,
provided, however, that property in parks may be leased for park purposes
to concessionaires, to charitable or nonprofit organizations, or to
governmental jurisdictions. All such leases shall require the approval of
Council as provided for in Article III of this Charter. No land acquired by the
City after December 31, 1955, shall be deemed a park unless specifically
designated a park by ordinance.