Happy birthday to London's St Paul's Cathedral, which was finished 300 years ago.
Well, it's finished apart from some of the decorating, anyway, but you know how it is with DIY.
London has many newer marvels - its Eye and its Gherkin - but I think the dome of St Paul's is still the best thing on the skyline.
A good word, dome. It always sounds to me as if someone has struck the huge bell-shape of it with an enormous clapper:
The word comes from the Italian word duomo, which means cathedral, and duomo is from the Latin word domus, which means house. I think the word's at its best in English, meaning dome, though.