Within 13 years, five were located along the San Antonio River. The missions’ purpose? To acculturate and Christianize the native population and make them Spanish citizens. Today, visitors can retrace the footsteps of the mission Indians and friars. And, possibly, meet descendants of those first inhabitants.The four mission churches within San Antonio Missions National Historical Park are active catholic parishes, and hold regular services. They are open to park visitors during park hours, except for special services, such as weddings and funerals.