or the "River Canyon".  It's located in Gualaca, Panama which is about a 40 to 45 minute drive from Boquete.  You'll be ready to cool off (it's much warmer there) when you arrive.  It's a great way to spend a 1/2 day or the entire day.  Take a picnic and relax.  There is no fee to play and you do not have to hike to get to it, park and swim!
(click on pictures below to view)