Sometimes abandoned man-made structures turn into dangerous eyesores, rotting away slowly before returning to nature or being torn down. Yet other times, like when abandoned ships are re-purposed as living reefs, or mines colonized by bats, abandoned structures take on a new semi-natural life all their own, like a crab with a jar for a shell. Such is the case with the Newnes railroad tunnel.

The Newnes railroad was closed in 1932 after 25 years of shipping Oil Shale. The rails were pulled out of the 600-metre tunnel which had been bored through the sandstone in the Wollemi National Park, and the tunnel was left to its own devices. In this case that meant thousands and thousands of glow worms.

The glow worm is a catch-all name for the bioluminescent larvae of various species. In this case the Arachnocampa richardsae, a type of fungas gnat which creates bioluminecse. Found in massive numbers in caves, the fugnas gnat larvae cling to rocky walls of the abandoned tunnel and hunt with long glowing strings of sticky mucus.

To see the glowing gnats enter the tunnel during daylight hours, to the middle - it gets dark in the middle where there is a bend in the tunnel - with a flashlight, so as not to bump into the walls, turn off the light and wait a minute or two. One by one they gnats will begin to shine like stars emerging in the night.

DETAILS AND DIRECTIONS

We'll be meeting at noon in Lithgow, NSW where State Mine Gully Rd and Atkinson St. meet. Lat/long: (-33.465684, 150.168269). From there, we will drive together about 25 km up Glowworm Tunnel Rd. and then hike 1km to the tunnel.

ABOUT OBSCURA DAY

Obscura Day is an international celebration of curious places happening around the world on March 20, 2010. It is sponsored by Atlas Obscura, a guide to the world's wonders, curiosities, and esoterica. To find out more about the Atlas and Obscura Day, or to find out how you can host an event in your city, visit ObscuraDay.com, or follow us on Twitter or Facebook.

While you are out exploring, we encourage you to take pictures and tag them on Flickr as Obscura Day and tweet using #obscuraday so we can all watch Obscura Day unfold all over the world.

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