Brisbane commuters may have access to underground shops once a planned new 19km cross-river rail project is completed, Premier Anna Bligh says.

The state government today announced it was planning to build an $8 billion underground rail tunnel from near Woolloongabba under the Brisbane CBD to Bowen Hills.

The proposed rail corridor. CLICK HERE TO SEE A LARGER VERSION

The premier made the announcement as part of the Cross River Rail study, which aims to find a new north-south connection in the inner-city.

A 19km proposed corridor would include a tunnel under the Brisbane River and new stations, running from Salisbury, in Brisbane's south, to Wooloowin, in the north, via Woolloongabba, the CBD and Bowen Hills.