Eltville City Wall and Round Tower

At the lower end of the Leergasse, the full height of the city wall is still visible. It was built in 1332 after the city was elevated. In front of the wall there was a moat 20 m wide and 5 m deep. For direct defense, the fortifications were supplemented at intervals of 80 m by half-shell towers, which are still present at the 'Yellow House' and 'Am Kiliansring'. The battlements were demolished in 1689. After that, houses were built on top of the wall.Source: resc.deskline.net/documents/1/RPT/48bbea5e-c614-4093-82a2-13db26141710/Rundgang_durch_die_historische_Altstadt.pdf

Absolutely worth seeing, because the Mumm family wrote wine history. Before the First World War, the Mumm family lived in Alsace, which was still German at the time. There they developed the famous sparkling wine called champagne.
After the First World War, the family was expelled and expropriated.
To this day there is a French champagne called Mumm.
Germany was forced to call sparkling wine (bottle aging) only Sekt and not Champagne.
The Mumm family moved to the Rheingau at that time.

At the lower end of Leergasse, the city wall rises to its full height. Here you can still find the remains of Eltville's city fortifications, which were built after the city was elevated to city status in 1332.
Source: eltville.de/freizeit-tourismus/erleben-entdecken/sehenswuerdigkeiten/eltville/historische-altstadt