Rapid Transit

What major and global cities have rapid transit/rail connecting their airports to their downtowns?

For example Vancouver is building Canada Line to extend their subway to their downtown core. What other cities do you guys know have similar transportation systems?

A great many cities have rail transportation from the (or an) airport to the city. Milan, Rome, Copenhagen, Frankfurt, Munich, Paris, Amsterdam, Vienna, … It’s not uncommon.

Dilated Peoples feat. Krondon – Rapid Transit