A view of the Lykens Valley Mine Tunnel entrance at Bear Gap, Dauphin County, Pennsylvania. This was the first site of commercial coal mining in the Lykens Valley and was the only mine in operation from 1836-1853. The tunnel was dug eastwardly into Big Lick Mountain. It continued in operation after another tunnel was dug westwardly into Short Mountain on the other side of the gap in 1853. Both tunnels were the main source of coal coming from the Lykens Valley until 1870 when two slopes were opened northward on either side of the gap.
The photo, from an old post card, shows unidentified men on a coal car returning to the mine. The car is pulled by mules, which were the primary power source for moving the cars in and out of the mine.
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