Dankwarderode Castle

In the 12th century, where the tower of Dankwarderode Castle is today, there was a castle chapel with a two-tower westwork. During his investigations in the 1880s, Winter found remains of the foundations of the castle chapel. Reconstruction was out of the question because there was no longer enough space due to the layout of the street. Through interlocking and unfinished components, however, he indicates that there used to be more.

Source and more info
braunschweig.de/tourismus/ueber-braunschweig/sehenswuerdständigen/_burg_dankwarderode.php

Henry the Lion had Dankwarderode Castle built as a residence between 1160 and 1175 based on the model of the imperial palaces. Over the centuries, the appearance of the castle changed greatly, partly due to a fire. Ludwig Winter therefore had it rebuilt in the neo-Romanesque style between 1887 and 1906.(Source: braunschweig.de/tourismus/ueber-braunschweig/gehenswuerdigkeiten/_burg_dankwarderode.php)

Dankwarderode Castle. The origin of the city of Braunschweig.