Sutro Tower

Before its construction, television reception in San Francisco was quite spotty, as the many hills of the city would block the line-of-sight radio waves — this was before the rise in popularity of cable television. Before Sutro Tower, transmitters were scattered throughout the Bay Area, including at San Bruno Mountain, Mt. Allison, Monument Peak, and Mt. Diablo. Reception outside of San Francisco was incrementally improved by the tower. By having all the main Bay Area television stations in one location, reception was improved by allowing all receiving antennas to be pointed at one tower instead of many. However, local NBC affiliate KNTV, which originally broadcast from Loma Prieta Peak in Santa Clara County, currently broadcasts from San Bruno Mountain to provide a strong signal to their city of license of San Jose. Most residents in San Mateo County, the East Bay, and Marin County can aim their antennas in the general direction of Sutro Tower and get all stations, including KNTV. Some residents in San Francisco need to rotate their antenna, as San Bruno Mountain is approximately five miles south of Sutro Tower.