During summer the river traffic is very heavy, even at night.
It is however opened many times a day in order to let through river traffic.
We have seen many changes, but one of the most important is the change in river traffic.
Today most goods are moved by truck and there is almost no commercial river traffic.
Of course, river traffic was different in the 1800s.
The railway journey was 1 hour against 2.5 to 3.5 hours for river traffic.
Upware had its own public house to serve river traffic by the 1760s.
River traffic and trade had built the city, and kept it going.
Following the growth of the railway river traffic fell into decline and stopped in the early 1900s.
Both are lifting bridges, which can be raised to allow river traffic to pass through.