Hamburg's parliament, senate and mayor all have their seats in the City Hall on Rathausmarkt. Convenient as that may seem, it took quite some time for this distinctive building to become the Hamburg icon it is today. After several relocations, fires and other turmoil, the current City Hall is the sixth edition in Hamburg's history.
Construction started in 1886 when 4,000 wooden poles were drilled into the muddy shores of the Alster Lake in order support the weight of the building, which would measure 133 metres wide, 70 metres deep and 112 metres tall. Special care was given to construct a passageway connecting the new building to both the Chamber of Commerce and the Hamburg Stock Exchange. The courtyard between these buildings resembles an Italian piazza and houses the Hygieia-fountain, named after the Greek goddess of health and built in remembrance of the cholera epidemic that swept through the city in 1892. After 11 years of labour, the City Hall with its 647 rooms was opened in 1897.
Luckily, you don't have to be a German politician to get a peek inside this eclectic, neo-renaissance building. Hamburg's City Hall is open to the public, and visitors may join a guided tour or visit exhibitions housed inside.
http://www.hamburg.com/sights/city-hall/