This is the (Catholic) cathedral in Saint Paul; I used to live just a few blocks away. For scale, the roof of the dome is the area of a football field.
DR singdaw, I loved The Duchess of Duke Street, which is loosely based on a real character. Gemma Jones, one of my favorite actresses, has a scene late in the series that will tear your heart out. Another series I liked very much is The Grand, which starred Susan Hampshire as a very discreet courtesan.