Brisbane train stations will be transformed into trendy subtropical hubs, with new shops and cafes, cycling routes and accommodation as a result of Queensland's "number one infrastructure project".

The business case for the $5.4 billion Cross River Rail project was finally released on Thursday, revealing more details of the new-look stations.

Cross River Rail's proposed Exhibition station at Bowen Hills.

The project includes a 10.2-kilometre rail line from Dutton Park to Bowen Hills, with 5.9 kilometres of tunnel under the Brisbane River and CBD.

There will be new underground stations at Boggo Road, Woolloongabba, Albert Street and Roma Street and upgrades of Dutton Park and Exhibition stations, with the project due for completion by 2024.