London The London Building acts of 1888 and 1894 ruled that architects should not be allowed to build structures higher than roughly 10 storeys to ensure the city’s finest landmarks were not obscured. London has grown upwards since then, but still has protected views that pinwheel around historic sites such as the Palace of Westminster, the Tower of London and St Paul’s Cathedral. These sight lines influence the volume and massing of new developments, defining the edges of clusters of towers and their dividing chasms