Camden House, Baker Street, London

“We are in Camden House, which stands opposite to our own old quarters.”
I had imagined that we were bound for Baker Street, but Holmes stopped the cab at the corner of Cavendish Square. I observed that as he stepped out he gave a most searching glance to right and left, and at every subsequent street corner he took the utmost pains to assure that he was not followed. Our route was certainly a singular one. Holmes’s knowledge of the byways of London was extraordinary, and on this occasion he passed rapidly and with an assured step through a network of mews and stables, the very existence of which I had never known. We emerged at last into a small road, lined with old, gloomy houses, which led us into Manchester Street, and so to Blandford Street. Here he turned swiftly down a narrow passage, passed through a wooden gate into a deserted yard, and then opened with a key the back door of a house.