Light rail system (56 km with 34 stops) operating 6 lines which share certain sections. Lines D, E and H run at all times, whereas lines C, F and G are not in service evenings and weekends.

Central corridor - 1994 - 8.5 km - 30th St/Downing - I-25/Broadway
Southwest corridor - 2000 - 13.9 km - I-25/Broadway - Littleton/Mineral
Central Platte Valley spur - 2002 - 2.9 km - 10th Osage - Union Station
SouthEast Light Rail - 17 Nov 2006 - 31 km - I-25/Broadway - Lincoln / Nine Mile

Regional Transport District (Official Website)

Denver Light Rail on Wikipedia (extensive description)

Thomas Gray's Map showing planned extensions