Montreal subway cars have four doors

Metro Cars
Originally uploaded by caribb

(which is something I advocate for in DC, for the WMATA system, to increase the speed at which people enter and exit train cars)

The subway in Montreal is all underground because the system wasn`t built to be weatherproof. Cars are smaller than in DC, but that allowed for cheaper construction in terms of required tunnel width.

They run on rubber tires. I guess the advantages compared to steel wheels are noise reductions and the ability to climb steeper grades. And the trains aren`t air-conditioned, which is noticeable this week...