Big Ben

A ventilation shaft was designed from the ground level to the bell tower.

An excerpt from the article 22 facts about Big Ben

The 4,9 m by 2,4 m shaft was designed by David Boswell Reid, known as the "grandfather of air conditioning". The purpose of the shaft was to draw cool, fresh air into the Palace of Westminster, but in practice, it failed. Until 1914, the shaft functioned as a chimney, which the shaft was converted into. In the years 2017-2021, conservation works were carried out on the shaft and an elevator was installed.