Maria-C, known as a 34 m x 9 m ship should fit comfortably into the port of Niendorf, a port close to my home at the Baltic Sea. So I sailed to this port, and I had to realize that the ship was bigger than expected! The fishermen from there said I should not go in, but I managed it with small scratches, both at ship and dock, which will multiply when I leave.
In Google Maps there is a measurement function, and Maria-C appeares as 56 m ship, as shown in the pictures below. As a kind of calibration, I also measured a track in the sports stadium, which measured 100 meters here, and Google is pretty accurate, the small difference comes only from my inaccuracy when clicking.