Spanish missionaries, soldiers, and families who settled San Antonio in the 1700s relied on the San Antonio River and irrigation ditches (acequias) to provide water for household and agricultural use. One of the earliest ditches, the Pajalache Acequia, originated near this site at a wide, shallow river crossing. A dam was built to divert water into a deep channel that flowed south to Mission San Jose, then located on the river's east bank. After San Jose was moved to another site across the river, the Pajalache Acequia carried water to Mission Concepcion, established on the east side of the river in 1731. The irrigation ditch operated until the 1860s, but after complaints that it contributed to flooding the dam was removed and the acequia filled in 1869. The nearby bridge and street are still called Presa, the Spanish word for dam.
Bronze plaques along the River Walk identify features designed by Robert H.H. Hugman. The plaques replicate the stamp that was imprinted on his architectural drawings. Hugman's initial concept for beautification and commercial development of the San Antonio River was conceived in 1929. Construction began on the River Walk project in 1939 with partial funding from the Works Progress Administration. To learn more about Hugman and the River Walk, please scan this QR code with your smartphone or go to