Located beneath the old Treasury Building on King William Street you can see a piece of Adelaide’s history. It’s an artificial subterranean tunnel supposedly linking the Adelaide GPO, the Treasury Building and the Torrens Building. The brickwork here is amazing. Tours are organized through the National Trust SA.

Keep up-to-date with what we’re exploring in and around Adelaide; and follow us in real time by following our Instagram feed: awesomeadelaide or our Facebook feed: Awesome Adelaide.

For those keen on underground exploration of tunnels, cavities, drains, mines, and caves, check out Adelaide's DARKSIDE Underground Exploring Group.

Also, to read more about awesome Adelaide places to explore, take a look at our Site Map.