Cremon was a marsh island in the Alster river at Hamburg, Germany. Today the site is marked by a street of the same name, in the Altstadt of Hamburg. The island was the first of the new town, and was outside the former city walls. The land was divided into long, narrow plots, on which typical Hamburg merchant houses were built. Each plot had access to the waterway later called Nikolaifleet. Behind the houses was a waterway called the , which was filled in during 1946. The waterway separating Cremon from the neighbouring island of Grimm, the , was also filled in after World War II.