The manhole covers in Rostock display the city arms. The coat of arms dating back to 1367 depicts a golden gryphon of a blue field (representing the former princes of Rostock). Bars of silver and red represent the colours of the Hanseatic League. As a member of the Hanseatic League, the city is named Hansestadt Rostock. [German]
Sources / More info
- Principality of Rostock (Wikipedia)
- City arms of Rostock (Wikipedia)