San Antonio Census Designated Place (historical) is a census located in Saipan County, Commonwealth of the Northern Mariana Islands. It appears on the Saipan OE W USGS 7.5-minute topographic quadrangle. The elevation at this location is approximately 12.37 feet (3.77 m) above sea level. The nearest populated place is Chalan Pi'ao, approximately 0.3 miles to the NW.