Wyandanch station was originally built in May 1875 as "West Deer Park". The station and tracks have always been at ground level. During the 1920s and 1930s, the vicinity of the station became the site of numerous horrific accidents involving crashes with trains at the unguarded grade-level rail crossings at Straight Path, 18th Street and Little East Neck Road. In 1935, after repeated protests from the people of Wyandanch, the Public Service Commission (PSC) ordered the LIRR to provide crossing guards at the 18th Street and Straight Path crossings during school hours on school days, so that school children living north of the LIRR to safely walk across the railroad on their way to the schoolhouse at South 20th Street and Straight Path on the south side.