The Tunnel, an expansive network of underground tunnels is one of many important historical landmarks in Labuan. This was the site where many of the island's coal mining activities took place for more than half a century."

The Tunnel was once a site frenetic with coal mining activities for more than half a century from 1849 through 1911. This expansive network of underground tunnels is one of many important historical landmarks in Labuan. Operated by various British companies for 64 years, it was during the administration of the New Central

Borneo, that an 8-mile long railway track was installed to Victoria Port to facilitate the export of the coal, resulting in a flourishing coal mining operation here. However, an unfortunate string of mining accidents led to the closure of the mine in 1911.

Today, what still remains in the area are pits and tunnels dug long ago, old bricks and pieces of rail tracks and rusted cables strewn on the ground. Visitors may enter a low tunnel with the help of a short rope and emerge from the top, although this should only be attempt with great caution. Across the road next to the Chimney, is a vertical well that is 10 feet wide, measuring some 100 feet deep. Entrances to more tunnels, which are yet to be explored, can be found at the bottom of this well.