It was San Francisco's nearest neighbor, less than two miles (3 km) away at the nearest point and easily seen from city streets, yet transportation factors rendered it effectively isolated. A boat could sail there in under half an hour, but wagons and carriages required an arduous skirting of the entire bay, a journey that could well exceed a hundred miles. As a result, the region was largely dominated by two disparate classes of people, both with ready access to boats: commercial fishermen and wealthy yachting enthusiasts. The first post office opened in 1870 as "Saucelito" and changed its name to the present spelling in 1887. In the 1870s, the North Pacific Coast Railroad (NPC) extended its tracks southward to a new terminus in Sausalito, where a rail yard and ferry to San Francisco were established. The NPC was acquired by the North Shore Railroad in 1902, which in turn was absorbed in 1907 by the Southern Pacific affiliate, the Northwestern Pacific. By 1926, a major auto ferry across the Golden Gate was established, running to the Hyde Street Pier in San Francisco. This ferry was an integral part of old U.S. Highway 101, and a large influx of automobile traffic, often parked or idling in long queues, became a dominant characteristic of the town. Northwestern Pacific commuter train service also expanded to serve the increased traffic volume, and Sausalito became known primarily as a transportation hub. This era came to an end in May 1937 with the opening of the Golden Gate Bridge. The bridge made large-scale ferry operations redundant, and since the new route of Highway 101 bypassed Sausalito entirely, in-town traffic was quickly reduced to a trickle. Car ferry service ended in March 1941 (passenger ferry service, however, continues to this day, linking downtown Sausalito with both the Ferry Building in San Francisco's Embarcadero, and Pier 39 in the Fisherman's Wharf district). Northwestern Pacific also closed its Sausalito terminal in March 1941, although some tracks remained in use as "spur tracks" for freight trains as late as 1971. Sausalito was a center for bootlegging during the era of Prohibition in the United States. Because of its location facing the Golden Gate and isolated from San Francisco by the same waterway, it was also a favorite landing spot for rum runners. The 1942 film "China Girl" has some footage of Sally Stanford's Valhalla restaurant on the waterfront. The scene shows the docks and illustrates rum running.