GPS with the National Park Service! When the missions were built in the 1700s, people had very little technology to help them map the South Texas landscape. Scientists now use new technologies like GPS to help study and preserve the missions! Come explore the mission and challenge yourself with our "GPS with the NPS" activity on Saturday, January 12! Earn your very own special Junior Ranger patch after completing the activities. The event is free, and participants may drop in at any time from 1-3 pm.