This Tower Is Not A Burger !

We left Berlin in the rain  and drove through more of the same towards Prague ..On seeing a McDonalds ( praise be for their coffee, choc cake and clean toilets ), we stopped .I spotted the above tower beyond the McCafe..at a place called Sireovich .At last my blip but what  was it ? 
I saw a Mcdonalds worker and our conversation went so :) 
ME ) Excuse me do you speak German ?
HIM ) Yes I do .
ME ) Please can you tell me what that old building is behind the cafe ?
HIM) McDonalds 
ME) No the old building the tower.
HIM)  A burger .it's a burger 
At this point I gave up and thanked him ( he  had tried ) 
Later I met this couple from Prague .( see my extra )They knew and were happy to tell me -The Windsor Mill which became a hunting tower and is now a protected monument is just that .IT IS NOT A BURGER::.Right now I'm in a hotel outside Vienna ...... It's been a strange day and a funny day .