Museum of Science and Industry (Chicago) of Progress event. For years, visitors entered the museum through its original main entrance, but that entrance became no longer large enough to handle an increasing volume of visitors. The newer main entrance is a structure detached from the main museum building, through which visitors descend into an underground area and re-ascend into the main building, similar to the Louvre Pyramid. In 1983, due to increased attendance, the museum started construction of its underground parking lot, located in three underground levels below the front lawn. Construction of the underground parking lot was finished in the 1990s. For over 55 years,
Paris in the Middle Ages not have an efficient system of covered sewers until Napoleon built them at the beginning of the 19th century. Street lighting was almost nonexistent in the Middle Ages. In 1318, it was recorded that there were just three street lanterns in Paris: one candle in a lantern outside the entrance to the Châtelet fortress; a candle outside the Tour de Nesle to indicate its entrance to boatmen; and a third lantern outside the Cemetery of the Innocents to remind passers-by to pray for the souls of the deceased. Very little light came from houses, since glass windows were extremely rare;