Martinsburg Castle, Lahnstein
Martinsburg, with its hexagonal keep, was built at the end of the 14th century on the banks of the Rhine and was once a toll castle. This picturesque ensemble was erected at the same time as the town fortifications. The pointed-arch gateway in the east wall still displays a small defence gallery with a coat of arms. Further elements of the building and towers were added between the 14th and the 18th centuries.