Top: The hydrotubes opened in August 1986 at Sportspark, just off Interstate 10 at the Ina Road exit. The indoor staircase led to three enclosed water slides.
Bottom: All that's left now is the tower, which looks like one very strange billboard.
If you miss the hydrotubes, you can find them at Marana's Breakers Water Park, 8555 W. Tangerine Road.
They've been there since April 1996, when Sportspark - losing money on the hydrotubes operation - sold the 1,110 feet of tubing to its former rival.

