Berlin is the capital and the largest city of Germany as well as one of its 16 constituent states. With a population of approximately 3.7 million, Berlin is the second most populous city proper in the European Union and the seventh most populous urban area in the European Union. Located in northeastern Germany on the banks of the rivers Spree and Havel, it is the centre of the Berlin-Brandenburg Metropolitan Region, which has roughly 6 million residents from more than 180 nations. Due to its location in the European Plain, Berlin is influenced by a temperate seasonal climate. Around one-third of the city's area is composed of forests, parks, gardens, rivers, canals and lakes. 

First documented in the 13th century and situated at the crossing of two important historic trade routes, Berlin became the capital of the Margraviate of Brandenburg (14171701), the Kingdom of Prussia (1701–1918), the German Empire (1871–1918), the Weimar Republic (1919–1933) and the Third Reich (1933–1945). Berlin in the 1920s was the third largest municipality in the world. After World War II and its subsequent occupation by the victorious countries, the city was divided; East Berlin was declared capital of East Germany, while West Berlin became a de facto West German exclave, surrounded by the Berlin Wall (1961–1989) and East German territory. Following German reunification in 1990, Berlin once again became the capital of all of Germany.
How many states does Germany have?
What is one of them?
Is it the capital?
Is it the largest city in  Germany?
Is it the largest city in the EU?
Is it the second most?
What rivers is it located on?
Where in Germany is it located?
What metro region is it in?
Is it in the European Plain?
How many residents does it have
How much of the city is nature?
When was the Margraviate of Brandenburg founded?
the German Empire?
the Weimar Republic?
the Third Reich ?
When was the city divided?
By what?
During what years?
When was Germany reunified?
16
one of its 16 constituent states.
Berlin
Berlin is the capital and the largest city of Germany as well as one of its 16 constituent states
yes
Berlin is the capital
yes
Berlin is the capital and the largest city of Germany 
no
 Berlin is the second most populous city proper in the European Union 
yes
 Berlin is the second most populous city proper in the European Union
the rivers Spree and Havel
the rivers Spree and Havel,
northeastern Germany
. Located in northeastern Germany 
the Berlin-Brandenburg Metropolitan Region
 the centre of the Berlin-Brandenburg Metropolitan Region
yes
Due to its location in the European Plain
roughly 6 million residents
Metropolitan Region, which has roughly 6 million residents
about 1/3rd
Around one-third of the city's area is composed of forests, parks, gardens, rivers, canals and lakes
1417
Berlin became the capital of the Margraviate of Brandenburg (14171701),
1871–1918
 the German Empire (1871–1918)
1919–1933
the Weimar Republic (1919–1933)
1933–1945
Third Reich (1933–1945)
After World War II
 After World War II and its subsequent occupation by the victorious countries, the city was divided;
by the victorious countries
occupation by the victorious countries, the city was divided;
1961–1989
surrounded by the Berlin Wall (1961–1989)
1990
Following German reunification in 1990, Berlin once again became the capital of all of Germany.