Hello,
I thought that you might want to know about a dataset that is being presented at the FGDC Coordination Group today. It is the Protected Areas Database of the United States (
https://gapanalysis.usgs.gov/padus/)
According to the Factsheet for the dataset (
https://pubs.usgs.gov/fs/2013/3086/), it is "The Protected Areas Database of the United States (PADUS) is the official inventory of public parks and other protected open space. With more than 3 billion acres in 150,000 holdings, the spatial data in PAD-US represents public lands held in trust by thousands of national, State and regional/local governments, as well as non-profit conservation organizations."
It is possible to download data for the entire US or a state from the Data page. Data can be downloaded in Shapefile or Geodatabase format (the Geodatabase format provides an MXD that can be opened to view the data).