Passage: As a devout Catholic, he joined the Centre Party in 1906 and was elected to Cologne's city council in the same year. In 1909, he became Vice-Mayor of Cologne, an industrial metropolis with a population of 635,000 in 1914. Avoiding the extreme political movements that attracted so many of his generation, Adenauer was committed to bourgeois decency, diligence, order, Christian morals and values, and was dedicated to rooting out disorder, inefficiency, irrationality and political immorality. From 1917 to 1933, he served as Mayor of Cologne and became a member of the Prussian House of Lords.

Question: In which area was he a Mayor of?
Cologne