I took two of my nephews to visit Lost River Caverns in Hellertown on a hot summer day. My music group, DayBreak, recorded one of our CDs in the cave a few years ago. http://www.daybreakfolk.com/LostRiverCaverns/lostCaveSessions.htm The cave provided a nice cool retreat on a hot summer day, & the boys loved it! Lost River Caverns' site: http://www.lostcave.com