Locally, the Greenbelt has some cool, cozy caving spaces favorited by enthusiasts, while the more claustrophobic might prefer the more open spaces found at Longhorn Cavern State Park. Only a little outside the city in Burnet, the park offers some pretty sweet guided tours, which are particularly good options, given it's probably easier to convince a date to venture into a cave with you in a group setting.
Take the big fall
Though a bit of an investment, skydiving is an action-packed activity resulting in glorious memories that will likely outlast your relationship. (You can do it nearby at Skydive San Marcos.) If your idea of a perfect date doesn’t involve having a stranger strapped to your back, iFLY offers an indoor skydiving experience that’s almost as good as the real thing. Added bonus: plenty of opportunities to use the line “I’m falling for you.”