<P> With almost 700 rooms, City Hall is the world's largest municipal building . The building houses three branches of government: the city's executive branch (the Mayor's Office), its legislature (the Philadelphia City Council), and a substantial portion of the judicial activity in the city (the Civil Division and Orphan's Court of the Pennsylvania Court of Common Pleas for the First Judicial District are housed there, as well as chambers for some criminal judges and some judges of the Philadelphia Municipal Court). </P> <P> The tower features a clock face on each side that is 26 ft (7.9 m) in diameter . The clock faces are larger in diameter than those on Big Ben which measure 23 ft (7 m). City Hall's clock was designed by Warren Johnson and built in 1898 . </P> <P> City Hall's observation deck is located directly below the base of the statue, about 500 ft (150 m) above street level . Once enclosed with chain - link fencing, the observation deck is now enclosed by glass . It is reached in a 6 - person elevator whose glass panels allow visitors to see the interior of the iron superstructure that caps the tower and supports the statuary and clocks . Stairs within the tower are only used for emergency exit . The ornamentation of the tower has been simplified; the huge garlands that festooned the top panels of the tower were removed . </P> <P> In the 1950s, the city council investigated tearing down City Hall for a new building elsewhere . They found that the demolition would have bankrupted the city due to the building's masonry construction . </P>

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