Hamilton Pool.

Oh my.  I just recently found out about Hamilton Pool, a swimming hole in Dripping Springs near Austin that is reputed to be "one of the most beautiful sights in Central Texas."  

"A steep path leads down Hamilton Creek, which winds its way between the pool and the Pedernales River along rocky ledges and over the roots of massive cypress trees." ~ from WimberleyTourism.com

Yes, PLEASE.  I'll be recruiting Dallas-dwellers to make this trip with us soon!