Along with Bridge 20, Bridge 21 is considered inadequate due to the height when there was a shift from shipping to car traffic. The lowering and widening was started and in July 1886 with the structures of both bridges being demolished and Bridge 21 was also lowered and widened at the same time. The project was completed at the beginning of 1887. It is now a girder bridge. Although of the same structure as the Anton Joling bridge, the latter is a municipal monument, and bridge 21 is not.
Amsterdam, Stadsarchief Amsterdam. The arch bridge by Hendrik Keun (1770)
Image 2 Amsterdam, Stadsarchief Amsterdam. Bridge 21 in around 1900.