Café Ciel

You're walking into the Old War Office building on Horse Guards Avenue—yes, that actual War Office—and somehow there's a proper French restaurant inside. Café Ciel sits within this Grade II* listed palace with soaring ceilings and the kind of grandeur that makes you second-guess your reservation. The room itself is theatrical: tall windows, ornate cornicing, that specific light you get when history's actually paying attention. It's the sort of place where you feel slightly better dressed than you did five minutes ago, but not so formal you can't relax into dinner.