Apparently, the city authorities had a referendum on whether to have a metro system, and it was voted down. So they then decided to find out how to persuade people to use the trams. They discovered that people didn't mind a slow journey, but wouldn't use public transport if they had to wait a long time for it - ten minutes at the outside.
So, Zürich trams run every 6 minutes. If you just miss one, you know that another will be along in 6 minutes. Not a bit before, not a bit after, but precisely 6 minutes!
Now, why don't these guys come and sort out London?

