The land and natural resources that exist within the borders of the states ought to be owned, maintained and used for the benefit of the people of the states in which they are located.
The federal government has taken control of:
8 parks in both AK and CA (16 total);
5 in UT;
4 in CO;
3 in AZ, FL and WA (9 total);
2 in HI, TX, WY, NV and SD;
1 in KY, ME, MI, VA, AR, MN, MT, NM, NC, TN, ND, OH, OR, SC and ID.
In addition to these parks, there are various 'national preserves' which ought to be returned to their appropriate jurisdictions. In the name of federalism, return these lands to the states.
There is precedent for this: Mackinac Island was returned to the state of Michigan in 1895 after being administered and maintained by the federal government.