If you’re feeling ambitious and need to work up a sweat (as a result of too many margaritas, perhaps), then head for the hills: Government Canyon is a 12,000-acre park and, incredibly, has hundreds of preserved dinosaur tracks. The trails are open to the public, and it’ll be about a three-hour hike to get to the tracks and back. In the summer months, be sure to go in the morning -- this is South Texas, after all, and it gets absurdly hot.
The River Walk is an obvious staple of San Antonio, but what a lot of visitors (and locals, even) don’t know is that there's more River Walk than what's featured downtown. Starting around the Pearl District, you can get on the less bustling end of the River Walk to see some of the amazing art installations under the bridges, including F.I.S.H. by Philly artist Donald Lipski. The best (and coolest, temperature-wise) time to see them is toward twilight, as the gigantic fish light up and it’s sort of like you’re walking underwater. This part of the River Walk also offers access to several museums. As a bonus, you can stop at open-air bars like the Luxury and bring your beverages on your walk. If you don’t feel like walking, feel free to hail a river taxi, but watch out: they’re a bit pricey.