10 Downing Street

The iconic black front door you see at 10 Downing Street hides a structural secret. While it appears to be a standard, modest townhouse, the building is actually a complex fusion of several different properties. In the early eighteenth century, the residence was joined with a larger, more elegant mansion that sits behind it, overlooking Horse Guards Parade. This resulted in a sprawling warren of over one hundred rooms, hallways, and staircases that extend far beyond the narrow facade facing the street.