Gardner Cave, the largest limestone cavern in the state, is the main attraction of 50-acre Crawford State Park in Pend Oreille County near Boundary Dam.
Tours of the cave are given at 10 a.m., noon, 2 p.m. and 4 p.m. The cave is closed Tuesdays and Wednesdays. Access to the cave is prohibited without a tour guide or after a tour has begun.
The guided tour season at the cave runs through Sept. 18. Tip: Even on the hottest days, take a sweater.