This private museum is hosted in a building designed by Italian architect Renzo Piano, and is a masterpiece of functional simplicity. The collection itself is one of the biggest in the world - only a fraction of which can be on show. It is an interesting juxtaposition to see Picassos and Rothkos together with intricately carved wooden figures and masks from Papua New Guinea, and it is not because of the primitive vs. the sophisticated: the carvings from PNG are not less intricate and sophisticated than the other pieces of art on display. (alas, some really "modern" pieces suffer as they are exposed as products of limited intellects, in comparison to the PNG carvings).
There is a good museum shop, selling interesting memorabilia, modern jewellery,books, etc.
Just outside Basel, can be reached by tram; the park is splendid in the spring - ample space for a picnic - even though the locals do not engage in such activity. A pity for them.