"Ian Jelf" wrote in message

In message , Tom
Anderson writes
Conversely, London never had the el-to-subway transition that built a
lot of the NYC system (there are one or two examples of this
happening in London, though).

I'll probably kick myself when you answer this.......but where are
there any examples of this happening in London?

How about where the District and Picc climb out of their subsurface and
deep level tunnels at Earl's Court to just below ground level at
Hammersmith and then up a steep gradient on to the viaduct by
Ravenscourt Park? Or where the Wimbledon Line climbs on to a quite high
viaduct in Fulham? And the Central west of White City?

In each of these cases, we have an Underground line climbing from a
tunnel to viaduct level, and staying at viaduct level for at least a few
stations.