# What is a bascule bridge?
**A bascule bridge is a type of moveable bridge in which the deck tilts around a horizontal axis to allow ships to pass beneath.** The word ‘bascule’ comes from the French for ‘seesaw’ or ‘balance’. The operating principle is similar to a seesaw: as one side goes up, the other side goes down.
## How it works
The bridge deck rotates around a pivot point (the trunnion). On the rear side of the pivot there is a counterweight that balances the weight of the deck. This means relatively little energy is needed to open the bridge. The drive mechanism is usually hydraulic or electric.
## Types
– **Single-leaf bascule bridge** — the bridge consists of one flap that opens from one side
– **Double-leaf bascule bridge** — two halves each open from one side and meet in the middle when closed
– **Rolling bascule bridge** — the deck rolls over a curved surface rather than tilting around a fixed pivot
## Application
Bascule bridges are widely used in the Netherlands due to its extensive waterway network, and are common in port cities worldwide. They are suitable where both road and waterway traffic needs passage.
### Advantages
– Fast opening and closing times
– Compact mechanism — no tall towers needed as with a lift bridge
– Low energy consumption thanks to the counterweight
## Related terms
– Bridge
– Drawbridge
– Lift bridge
– Swing bridge
– Pontoon bridge
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