London's Garden Townhouses Have a Secret

London sells itself on its facades, but its secret is behind them: the great communal gardens, locked and leafy, that a row of townhouses shares like a private park. A key to one of these is worth more than any number of reception rooms.

It is the urban relative of the impulse driving Lake Como's garden estates and the vernacular houses of the Cyclades: buy the planting, not just the plot.