Avenue Foch (French pronunciation: ) is a street in Paris, France, named after World War I Marshal Ferdinand Foch in 1929. It is one of the most prestigious streets in Paris, and one of the most expensive addresses in the world, home to many grand palaces, including ones belonging to the Onassis and Rothschild families. The Rothschilds once owned numbers 19-21. It is located in the 16th arrondissement and runs from the Arc de Triomphe southwest to the Porte Dauphine at the edge of the Bois de Boulogne city park. It is the widest avenue in Paris and is lined with chestnut trees along its full length.