Prior to around 1915, the Coos region was largely isolated from the rest of Oregon due to difficulties in crossing the Coast Range and fording rivers, and the Pacific Ocean was used to link people to other areas, including San Francisco, which was an easier two-day trip compared to traveling inland over rugged terrain. In 1916 a rail line was completed that linked the region to other interior settlements and towns, which increased commercial trade and tourism Significant urban growth occurred in the 1920s, and during the 1930s to 1950s large-scale growth occurred. Per the Oregon Bay Area Chamber of Commerce, during the 1930s to 1950s: