highway to improve their access from the Naval Air Station on Boca Chica Key to the mainland for national security purposes. The 1920s-era lower keys segment was less than ideal with its winding road and rickety wooden bridges. This resulted in completing the rest of the highway throughout the keys on the former railroad right of way, which the state already owned and was a more direct route with smoother curves that would allow for higher speeds. Also included in this project was the construction of the highway from Florida City to Key Largo on the old railroad route via Jewfish Creek, which shortened the route from Key Largo to the mainland by 17 miles. The new alignments were officially completed on May 16, 1944, with Florida Governor Spessard Holland presiding over ribbon-cutting ceremonies. The original Card Sound Bridge was closed after the Jewfish Creek alignment opened, and its remains were subsequently destroyed by a fire (the Card Sound route would be restored as a secondary route in 1969 with the opening of the current bridge). Today, some segments of the original highway remain as side and frontage roads for the current highway. The original highway through Key Largo and Tavernier would once again become part of the Overseas Highway in the early 1970s when it was expanded to a four-lane divided highway. Here, the northbound lanes run along the route of the original highway and the southbound lanes along the route of the railroad, which is especially evident in area where the route splits into two one-way streets. The widening was the beginning of a much larger project to rebuild much of the Overseas Highway, which included replacing the aging repurposed railroad bridges with more modern bridges; some of which are able to accommodate more than two lanes of traffic. This included the Seven Mile Bridge, the Bahia Honda Bridge and the Long Key Bridge (although these three original bridges are no longer open to vehicular traffic, they became listed on the National Register of Historic Places in 1979 and are currently used for fishing and pedestrian traffic). The more modern bridges were completed in the early 1980s. In recent years, Pigeon Key was used by the University of Miami as an oceanography laboratory, but current efforts to restore the buildings on the island have resulted in the establishment of a railroad museum there. The newer Seven Mile Bridge