Big Bend Ranch State Park is the largest state park in Texas and offers outdoor recreation for the truly adventurous. It is a remote park along the Rio Grande, where visitors ride bikes through the Chihuahuan Desert, raft or paddle the river on the border with Mexico, explore on horseback and camp in perfect solitude. Park headquarters was once the headquarters of a working ranch, complete with the owner's home. Day passes are available online, and permits are picked up at the visitor center.