Is the Brit Rail Pass valid on London Subway trains also?
In short, no. The Oyster card only covers London Transport bus, tube(subway), Docklands Light Railway and the Tram system. As yet, there’s no cover for overground railway (Brit Rail) included in this, but you can buy ‘through tickets’ with British Rail which will enable cross-City travel on a ~specific~ route rather than ~any~ route. So it depends on whether you merely want to pass through London on your ‘through’ ticket (for instance, if you arrive at Victoria which is both a tube station and a British Rail station but need to travel from Victoria to Paddington, which is also a tube and British Rail station, then you purchase a ticket from Victoria to your out-of-city destination [say, Exeter in Devon], then your ticket will also entitle you to travel by tube ONLY between Victoria and Paddington), or do the tourist bit with a go-anywhere Oyster which will help you tour anywhere IN London for the period of its validity.
