Museum of South Texas History

The museum opened in 1967 as the Hidalgo County Historical Museum in the old county jail on Closner Boulevard, built in 1910. The jail is still one of its most important sections and has its own exhibition. In 2003 a $5.5 million addition of 22,500 square feet gave it a lobby, a store and permanent galleries, and the museum took its present name to match the region it covers, the Rio Grande Valley and the lands between South Texas and northeastern Mexico.

The permanent exhibit is Rio Grande Legacy, with bilingual text. Its first sections opened in 2003. River Frontier begins with the region's geology and ancient life, then turns to native peoples and the Spanish frontier of New Spain. River Crossroads, the last section, covers the rapid changes of the 20th century. Other displays include prehistoric plant and animal fossils and a replica of a river steamboat.

The museum keeps its papers in the Margaret H. McAllen Memorial Archives, and prospective donors can consult its donation FAQ. Outside is the Will Looney Legacy Park, and the museum publishes a podcast, Stories from the Rio Grande, and holds talks called Museum Pláticas. It is accredited by the American Alliance of Museums. The building is wheelchair accessible, and the museum is closed on Mondays.