From Tate Britain, a nicely painted picture of London at the start of the last century, just before the big war. Printed beside the painting :

Philanthropist Henrietta Barnett devised Hampstead Garden Suburb, built in 1907, to provide mixed housing in pleasant surroundings in outer London.

William Radcliffe page at The Tate.

How times have changed. I wonder how "mixed" it is now, or how affordable?