It’s been the case since the flood in 2008, but today it was official.
The Cedar Rapids city government is now headquartered in the old federal courthouse. Before now (before 2008, that is), it was located on Mays Island.
For much of the 20th century, it was reported/believed that there were only two cities in the world that had their government located on an island in the middle of a river: Cedar Rapids and Paris. That Paris. In 2003, a visitor from Iowa to Osaka, Japan, said that city could also qualify.
Now, at least for Cedar Rapids, that is no longer true.