The Gouwe Aqueduct near Gouda passes above the A12 Highway. It carries the Gouwe River across the freeway, as well as the barges and sailing boats floating upon it. And occasionally a huge yacht will cross over the highway, providing quite a spectacle for anyone driving below it.

In 1938, a bascule bridge was built over the Gouwe, allowing the new four-lane A12 Highway to complete its route between Moordrecht and Gouda. When opened, the drawbridge could let boats pass by along the newly bridged Gouwe. By the mid-1960s, however, traffic had increased significantly, and the bridge-openings were causing huge traffic jams.

Plans were made to expand the capacity of the A12, but that would also require a new way of crossing the Gouwe. The expanded highway was deemed too large for a bridge, so it was decided that the river should go over the highway, rather than vice-versa.

The project began in 1975 and the Gouwe Aqueduct was opened to traffic on October 6, 1981. It soon became one of the busiest aqueducts in the Netherlands.

The entire construction stretches for about 700 meters, with some 70 meters crossing the actual highway. With a width of about 155 feet (47.35 meters), the aqueduct can accommodate surprisingly large vessels.

The image above shows the crossing of the Symphony, a 333-foot-long (102-meter) yacht on its way from Kaag to Rotterdam. For drivers on the eight-lane highway below the aqueduct, seeing a superyacht slowly crossing above them was a surreal sight indeed.