Zagreb tram, a photo by zannnielim on Flickr.

The Zagreb Tramway, run by the Zagrebački električni tramvaj (ZET), consists of 15 day and 4 night lines in Zagreb, Croatia. Trams operate on 116 km of meter gauge tracks. During the day every line runs on average every 5–10 minutes, but almost every station serves at least two routes. Nighttime lines have exact timetables averaging at about every 40 minutes. The first horsecar tram line was opened in 1891, and the first electric tram ran in 1910. Zagreb's tram system transported 204 million passengers in 2008. (source: wikipedia)