RE: Senior Passes for Parks
Seconding Al's comments on the Golden Age Pass.  Got mine just under a month
early, a cooperative gate attendant at Grand Canyon...
Use it whenever I can.

And some States have program.  Don't know about other States but here is a
summary of what The Soviet of Washington (not my woeds, the words of Jim
Farley, FDR cabinet member, the Carl Rove of his day) offers:

http://www.parks.wa.gov/passes.asp

Note that you have to qualify for a Senior Citizen Property Tax Exemption
before you get the Senior pass.
BTW, from an old Assessors Deputy.  There ain't no such thing as a true Tax
Exemption for senior.  The State and County still get ALL their money.  If
the senior citizen qualifies to not pay it that dollar amount is collected
from the neighbors, they pay it.  It's really a Tax Shift not an Exemption.
The Legislature was not about to give up a dime of tax money they could
collect to use to bribe the voters with 'benefits' and thus keep themselves
in office.  The way this is done is complex, pmail if you want details.