The Magere Brug is a bridge over the Amstel Canal in Amsterdam. The current bridge was built in 1934 and appears in Diamonds are Forever.
The scene in the film featuring the bridge begins with a tour boat cruising along the canal with the tour guide being heard describing the history of it. The tour guide is interrupted however when when the body of diamond smuggler Mrs. Whistler is being removed from the canal. We then see a shot of Mr. Wint and Mr. Kidd standing on the Magere Brug posing as tourists and observing the events.