An abandoned train tunnel is now filled with bioluminescent bugs. Flooded train tracks lead to an abandoned passageway, almost lost in a cascade of greenery. Once inside, a charming blue glow illuminates the dark, dank tunnel. Officially called the Metropolitan Tunnel, this underground passage was built in the 1880s. Its use was short-lived, as it closed in 1915 after years of soot and smoke accumulated inside, making it dangerous for train crews and passengers to pass through. One end of the tunnel was sealed so that it could become a reservoir. The northern entrance was also blocked due to years of dirty debris building up outside. The entire tunnel was almost hidden behind a thick veil of lush flora. Before it was drained and partially cleared in 1995, the entire passage was filled with standing water.

But the tunnel hasn’t been completely abandoned in that time. A colony of glowworms – one of the largest in all of New South Wales – has moved in and taken up residence on the roof.

The tunnel still floods quite often. On days when the water level is particularly high, people walk over the small waterfall that often falls through the entrance after heavy rains, carrying pool floats or inflatable canoes.