Rententurm

Defense tower of the late Gothic city fortifications at the landing stage for the market ships

The former gate tower that secured the former Fahrtor is now part of the Frankfurt Historical Museum.

At the end of the Eiserner Steg, at the former Fahrtor east of the Leonhardskirche, you can see the so-called Saalhof. It is one of the most historically interesting quarters of the city as it emerged from an old Stauferburg. This was clearly recognizable as such until the 18th century. Today the rent tower standing at the left end and a Romanesque chapel behind the buildings still bear witness to this. Only between 1715 and 1717 was the Bernus Building built next to the tower instead of the castle wall, followed by the Burnitz Building, built in neo-Romanesque style from 1840 to 1842.
The Saalhof is known as the seat of the Frankfurt Historical Museum. This museum facility is so large and extensive that the Saalhof is not enough for the exhibitions - although it is "only" about the history of Frankfurt. But it is so exciting simply because the German kings and emperors have been crowned in the city for centuries. The following main exhibitions can be seen here: Frankfurt in the Middle Ages, Frankfurt in the Late Middle Ages, 16.-18. Century, immigration and coexistence as well as Frankfurt city history 1866 to 2001.
An additional building was even erected in 1972 to expand the exhibition. This was - typical for Frankfurt - torn down again because of its controversial architecture. A new building is now at this point. And because the exhibitions in the Historical Museum are so extensive, guided tours are even offered.

Source: Quermania