Two weeks ago my daughter and I had a reservation at The Barnes Foundation, just outside Philadephia. I'd heard this was a remarkable and little known collection. It was fantastic. The building was built to house the collection, there's a large mural by Matisse painted on site, and each room was designed to be a masterpiece.
By that I mean that the arrangement of paintings, furniture and objects in each room was carefully thought through. It's not possible to describe the quantity of masterpieces. They don't allow photos, you won't find much online, I bought cards and scanned a few for my blog. Look again at the paintings above. The Toulouse-Lautrec is unlike his poster art. The Rousseau flowers seem barely contained (the asters look like tigers to me! Rousseau's paintings seem never to get far from the jungle.) The Gauguin boy in his splended clothes but oh, what a background! There are hundreds of Renoirs, a significant collection of Cezanne, Matisse, Pissarro, Modigliani, Picasso and so many others.
If you're anywhere near here, you must visit. Reservations are required and they tend to sell out in advance. There are plans to move the collection to a new building. I'm glad I saw it before the move.