This is an incomplete list of routes which have been released, so please help me to fill in the gaps. They are listed in alphabetical order by their more recognisable name with the DLS name in brackets if different to aid searching.
Name - Region - Era - Creator - Location
Prototypical Routes
Fort William to Mallaig - Scotland - 1980s - Vern/TMZ06003 - DLS
East Coast Main Line - Eastern - 1970s - DPS - Builtin to TS2010
Settle and Carlisle Railway - Midland - 1960s - Railsim - S&C Addon/Builtin to TC3
West of England Main Line (On DLS as West Coast Line) - Western - 2000s - Angelah - DLS
Colne Valley - Skipton - Northern (KUID:238039 on DLS, 3 parter)
Colne to Skipton Pt1 238039:1494
Colne to Skipton Pt2 238039:1514
Colne to Skipton Pt3a 238039:1012
1960s Yorkshire by clack45 on the DLS. Merge them together to give a decent run between Colne and Grassington via Skipton. Unfortunately though it can't easily be merged with the S&C route as the ground heights are different.