The USS Denver was a Federation transport that was in service during the late 24th century.
On stardate 45587.9, the Denver was hit by a Cardassian gravitic mine while transporting over 500 colonists. The USS Enterprise-D responded to the disaster and provided medical assistance to the survivors. (TNG: "Ethics")
Background
The Star Trek Encyclopedia describes this vessel as a Yorkshire-class starship, with a registry of NCC-54927.
This ship was possible named after the county and city of Denver, Colorado in North America.