Once the path of a railway tunnel, now home to thousands of glowing insects.

By standing on a particular paving stone in the courtyard, you'll hear an echo that shouldn't be.

A series of gun powder chambers currently hidden from view within Nobbys Headland in Newcastle, Australia.

An abandoned railroad tunnel is now filled with bioluminescent bugs.

A sparkling sandstone cliffside that's worth a visit while it still exists.

A defensive fortification carved into a cliff near Sydney Harbour.

The yawning remains of a complex naval fortress still haunt this Australian shore.

An ancient rock engraving shows Aboriginals used their advanced knowledge of the stars to hunt and gather.

Nature is leading a successful mutiny on this century-old freighter.

A boardwalk winds through this sliver of coastal nature hidden within Sydney.

This secret Australian garden was built on love after a man planted a random bulb he found in the ocean.

Built over an abandoned train yard, this hidden gem is full of winding paths and offers gorgeous views of Sydney Harbour.

An ancient engraving by the Cammeraygal people was uncovered in the transformation of a North Sydney industrial site.

Ninety years of Sydney buses under one roof.

One of Australia's largest secondhand bookstores.

This odd 1930s shop remains stranded in time and shrouded in mystery.

This historic observatory contains the world's oldest refracting lens telescope.

The world's first indigenous rooftop farm boasts 2,000 plants from more than 35 different native Australian species.

Hidden among popular Sydney golf courses is a little remembered graveyard populated by smallpox victims.