the Walter Taylor Bridge is the only habitable bridge in the Southern Hemisphere, it's in Brisbane Australia (I've been there! Never heard of this!)

The original toll master and generations of his family lived in the unusual family home in the pillar on the Indooroopilly side of the bridge for 74 years. The pillar on the Chelmer side of the bridge contains another dwelling, as well as a ballroom underneath the bridge.

https://www.atlasobscura.com/places/walter-taylor-bridge