3. Villa Cook
If you have time, whilst you are in Boulogne-Billancourt, we recommend strolling over to the Villa Cook, another of Le Corbusier’s purist villas, built in 1926 for an American journalist. It also develops all the principles that later became his Five Points (the open section of the ground floor has since been filled in). Even though it’s not open for visits it’s well worth the trip, as it’s sandwiched between two other spectacular modernist villas, the Villa Collinet (1926) by Robert Mallet Stevens and the Villa Dublin (1929) by Raymond Fischer.
Have a break for lunch, and then take the metro across town to the eastern side of Paris.