Riding the AirTrain in San Francisco's Airport

We were very early for our flight from San Francisco to Toronto, so instead of exiting the AirTrain at our designated stop, we decided to cruise around for a while, terminal-to-terminal, on a very typical, overcast rainy San Francisco morning.

The SFO AirTrain is a 24-hour automated people mover to transfer between terminals.

The stops are all only minutes apart.

It was opened in 2003 at a cost of US $430 million.

There are a total of 38 cars coupled in trains of up to three cars.

The tracks cover a total of 6.4 miles (10.3 km).

The train is free of charge. It is funded by a $20 "airport fee" charged by car rental companies.

So if you are ever really early for a flight - like we were - why not AirTrain around for a while?