Boston in the USA has an underground. It is approx:
- 20 miles underground, inc' a direct underground link to the airport. Most of the network is overground.
- Around 120 stations.
- Has street running tram-trains, that also run underground. Although they are not that pretty.
Quite impressive for a city of 650,000.
Liverpool is approx 450,000. with 68 stations and about 6 miles of underground tunnel.
Liverpool can have about 10 miles underground using disused tunnels and also approx 120 stations when disused surface lines are used.
It is about time the city caught up. The city can do is cheaply as well.
Cutting road schemes and using the money to expand the rail will encourage people to use the rail system - along with computer ticketing like London's Oyster card, which Merseyrail is looking into.