farms. However, during the droughts of the 1930s, individual farmers moved away from Promontory, leading to the consolidation of their lands into large holdings. Decline Although Union Pacific engineers had initially considered a direct route across the Great Salt Lake, cost and schedule constraints forced them to opt for the surveyed line through Promontory. As trains became longer and heavier, additional engines were often required to pull them along the winding curves and up steep grades to the Promontory summit. This changed when the Southern Pacific, which had acquired Central Pacific operations in 1885, built a wooden railroad trestle across the Great Salt Lake between Ogden and Lucin, between February 1902 and March 1904. The Lucin Cutoff completely bypassed Promontory Summit. The last regularly scheduled transcontinental passenger train to pass through Promontory station was on Sunday, September 18, 1904. When the Great Depression led to a dramatic fall in revenues from railroad traffic, the Southern Pacific decided to abandon the line when it failed to meet its operating costs. On September 8, 1942, an "unspiking" ceremony was held to commemorate the lifting of the last rail over Promontory Summit; the old steel rails were used for the war effort in World War II. In the 1950s, the wooden trestle was replaced with a parallel concrete-stone causeway built by the Morrison-Knudsen construction company. Southern Pacific continued to maintain the wooden trestle as a backup for several decades, although its last significant rail traffic was in the early 1960s. By the 1980s, the trestle's condition had begun to seriously deteriorate. Beginning in March 1993, the timber from the trestle has been salvaged and removed. Preservation By the early 1950s, a number of re-enactments of the driving of the last spike had been held at Promontory Summit. The renewed interest led to a concerted effort to save the historic site. In 1957, local campaigners succeeded in getting the area recognized by the federal government, but without federal land ownership. The Southern Pacific, which still owned the right of way, agreed to give its holdings to the federal management. On July 30, 1965 the Act for the Golden Spike National Historic Site was signed into law. The area is administered by the National Park Service. On the 110th anniversary of the "Golden Spike" on May 10, 1979, two purpose-built replicas of the UP #119 and the Jupiter #60 were brought together on a specially