Water slide carved into the side of the city’s dam on the Comal River, with a tube rental facility. Best time to go is early! It can be packed very quickly. It is also totally safe to swim down without a tube. It is, however, where Ben busted his lip, so just be smart.
Best pub food and most bestest list of local(ish) beers. Good taste of Texas. If you are staying up north, this is a lovely oasis in the sprawls of suburbs and concrete.
One of the oldest Cathedrals in the country. The city is literally built around it. The river walk is an easy walk from it, too. They have confession 10a-5p every single day.
The mission trail can be biked or hiked. It'll probably take a full day to bike the entire trail. There are multiple entries and exits. The website also provides links to bike rentals and such.