The Rockaway beach area has played a role in local history since the arrival of the Portola Expedition , the Spanish explorers credited with discovery of the San Francisco Bay . As early as 1776 , limestone was quarried in the Rockaway Beach lime pits and was used to whitewash the newly built Presidio of San Francisco . More recent investigations suggest that early settlements in San Pedro Valley also used this limestone for their foundations . In 1907 , the Rockaway Beach quarry was established as a continuously-operating commercial entity known as the Stone Brothers . After construction of the Ocean Shore Railroad in 1907 , limestone from this quarry was conveyed to assist with the rebuilding of San Francisco after the 1906 San Francisco earthquake . Quarry materials were actually used as ballast for the trackbed of the railroad ; moreover , after completion of the railroad , Rockaway Beach was considered a suburb of San Francisco due to convenient access . This all changed after legal problems resulting from landslide repair caused the railroad to go bankrupt in 1921
1906 San Francisco earthquake
1906 San Francisco earthquake
Rockaway Beach, Pacifica, California