Presidio, there's a unique and beautiful historic site, Fort Leaton. From the TPWD website, "In 1848, Ben Leaton built a fortified adobe trading post known as Fort Leaton. He dominated border trade with the Apache and Comanche Indians before he died in 1851."
Photographers love this spot along the Rio Grande because of the way the light looks on the adobe walls, and the contrast with the deep blue skies most days.
If your travels take you to Hwy 170, the River Road, plan to include Fort Leaton on your itinerary!