The Skinny Bridge, or Magere Brug in Dutch, is Amsterdam's most famous bridge. It crosses the Amstel river between Keizersgracht and Prinsengracht.
The Skinny Bridge is a wooden bridge in a typical Dutch design, known as a double-swipe bridge. It has two sides that can be opened, and usually are simultaneously, and counterweights to balance the weight and make it easier to open.
Myth has it that it is named after the Mager sisters who lived on each side of the Amstel, and wanted to have an easy and direct way to visit each other.
This should probably be taken with a grain of salt. It is more likely that the bridge was named after its shape when it was first built - a narrow, "skinny" bridge that hardly allowed passing pedestrians to pass each other.
Today it's somewhat different. Altough you can't drive across it, the current bridge built in 1871 is wider than its predecessor and easily allows bicyclists and pedestrians to cross.
This type of bridge can be found five other places in Amsterdam. Most older bridges only have one section that can be opened - the single-swipe type.