Renamed in 1913 from its original name of Yarronvale, Cooladdi predates the 'Flying Flea' steam train from Charleville to Quilpie. In its heyday as a major rail centre, Cooladdi boasted a school, butcher shop, post office, store and police station accommodating 270 residents. The railway bypassed the town in 1914, starting a long decline. A Cooladdi State School which opened in 1970 was abandoned in 1974.
Now the smallest town in Australia, Cooladdi has its own motel, train station, general store, self-rated four-star restaurant, pub and just four residents.
Access is by road, from Charleville — approximately ninety minutes distant. The train no longer runs.
- Cooladdi rail station. No longer in service, but the building and rails are still standing.
- Cooladdi Heritage Trail. A walking tour of the city. A written guide and map are available at the Charleville Visitor Information Centre, Qantas Drive, Charleville.
- Fox Trap Cooladdi Roadhouse, Diamantina Development Highway, Cooladdi 4479, ☏ , . Motel with bar and restaurant, grocery and post office.
- Cooladdi has its own post code, 4479, with a small post office in the Fox Trap motel. It is the smallest point in Australia with a post office.