10am mostly till dusk. 6 7pm. The tower you may take the elevator up to an half hour before closing 8pm. Plan on a minimum of an hour to explore all the information on the 2nd. Floor. Enjoy!
The trail system of the park 'closes' at 10pm I believe, but the city of Hot Springs and the sidewalks are always 'open'. A fun fact is that the water's average temperature coming out of the hot springs is 143°F!
The park is always open. The city of Hot Springs is the national park.
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