Ah, the signs of spring are already sprouting: Adventure Island water park is opening for the season, and so is Legoland's. At Adventure Island, they are marking the day with the first Tampa Bay Kids Triathlon. Starting at 7 a.m. on Saturday, kids will be divided into two divisions to run, bike and swim around the Busch Gardens-owned water park. The swim takes place in the Rambling Bayou (better known as the lazy river), where the water is heated (whew!). Entry fee is $35 at tampabaykidstriathlon.com or $40 on the day of the event. After the race, the water park opens for the season, 10 a.m. to 5 p.m. Saturday and Sunday. Legoland is opening its water park for the second year at 9:30 a.m. Saturday, included with park admission. There is a Lego-themed Build-A-Raft River, the Joker Soaker water playground, a 583,000-gallon wave pool and five slippery-fast water slides. Admission to Legoland is $75, $65 seniors and ages 3-12 (Florida residents can get a $99 yearlong pass) in Winter Haven. Toll-free 1-877-350-5346. Adventure Island is at 10001 McKinley Drive, Tampa. One-day tickets are $41 adults, $37 child if purchased online at adventureisland.com.