High Quality Content by WIKIPEDIA articles! The Pachuca`s Monumental Clock is a clock tower 40 m high, located in Plaza Independencia of the Historic centre of the city of Pachuca, in Hidalgo State, Mexico. Which was built between 1904 and 1910 to commemorate the Centennial of the Independence of Mexico. Its machinery is identical to that of Big Ben in London. The Monumental Clock is the best known symbol and representative of the city.