WATER WORLD Take to the water the Texas way this summer—in a tube on a river. If you want sustenance afterward, check out these three favorites of ours. The behemoth of Central Texas river restaurants is the 950-seat Gristmill in the historic hamlet of Gruene, on the Guadalupe. With nearly half its seats overlooking the water, the Mill feeds famished floaters with better-than-decent mushroom quesadillas, onion rings the size of wagon wheels, and entrées like tomatillo chicken breast. Way out west, tubers on the Frio River can keep their laid-back mood going at House Pasture Cattle Company, in Concan. The whole point here is to sit out on the sprawling covered concrete slab and nurse a beer while listening to the classic jukebox or the summertime live-music lineup. The food ranges from basic CFS and Buffalo wings to quail stuffed with cream cheese. And after a day on the San Marcos River, nothing satisfies a big appetite better than a regular dinner or cheesy enchiladas at Herbert's Taco Hut. Lots of AC and a cold drink make for a nice reprieve from the heat. You won't need to wear your shades—there's not a glimmer of sunlight in the place.