One Albermarle Row. The entire terrace is Grade II* listed apart from number 1, which is clearly a later addition, and merely Grade II listed. It might have looked less of the odd one out when it was hugged by 4 Cumberland Place on the end, but it seems strange to have chosen such a different architectural style, and that big bay window in the middle is odd.

2-9 Albermarle Row were built in 1763 (there's a big plaque in the pediment of number 5 that bears the date, which I've already snapped). The listing for Number 1 says:

Attached house. 1812 on deeds. Brick with limestone dressings, party wall stack and pantile mansard roof. Originally single-depth plan, since extended behind. Late Georgian style.

I think the thing I'm most curious about—and which will presumably remain a mystery—is the renumbering that must have happened. Was Albermarle Row numbered 1-8 from 1763, and then when this parvenu pitched up in 1812, everyone moved their door numbers down one to make room? I'd've expected this to have been dubbed 1B, or something like that...