I'm now the proud owner of a National Parks Lifetime Senior Pass which provides entrance or access to myself and accompanying passengers in a single, private, non-commercial vehicle at Federal operated recreation sites across the country. If you're 62 years old or better and love the outdoors, this is a real bargain for $90 for the rest of your life. My first visit, in the planning stage, will be Fort Sumter in Charleston, SC.
https://store.usgs.gov/senior-pass