At keast two hours. There is a daily tour at 1pm.
3 hours. Lol.
Plan on a couple hours, minimum.
Bring a picnic lunch. Lots of tables under huge oak trees. Easy walking. I'd plan a minimum of 2 hours,of course you can stay as long as you like. At end of your tour visit the onsite museum for lots of park information/history. A very nice day outing and well worth the stop!
I spend like 3:30 to 4:30 hours to see all the buildings since I parked my car.
If you hurry, an hour. Two is great. You don't need a guided tour to enjoy or understand it, especially if you have antsy young kids. It would be a bonus if you had time.
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