Expect to see Alexander Calder mobiles mixed into a Peter Fischli and David Weiss display, or pieces by Paul Klee and Claude Monet side by side with contemporary artworks from Wolfgang Tillmans. There’s no one set theme at the Fondation Beyeler, Basel’s glassy, Renzo Piano–designed temple to creativity, on grounds graced with bucolic trees and greenery and stuffed to the gills with blue-chip art. The foundation was established by Basel art dealers Hildy and Ernst Beyeler and is arguably one of the most important contemporary museums in Switzerland. The exhibitions timed to coincide with Art Basel (in mid-June) are often some of its best.