All day, it is a tour on your own, or you can request a tour on the hour.
Do it before 4.30pm for sure else you won't get a guided tour of the Texas White house. Everything else is self tour.
As far as I know, there are no tour hours for the park at all. The park is totally self-guided. The guided tours are for the Texas White House. For these, you show up at the Hangar on the Ranch and book. Either the next one available or any later one. Be advised, there is quite a crowd now, during spring break.
10am-5
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