The Kimball Art Museum in Fort Worth, Texas, designed by architect Louis Kahn, is considered by many architects as one of the best examples of modern architecture in the United States. Natural light enters at the top of the barrel vaults which are actually barrel shaped beams. The light is then diffused and directed to reflect off the cast concrete beam which illuminates the space below. The natural light is supplemented with artificial lighting to balance the art viewing levels.
Currently there is an addition being built beyond the back courtyard, so I wasn’t able to experience the outdoor courtyard on this visit.
Only one of the two gallery wings was open when I was there. They mentioned that much of the art was in storage, but the pieces they did have on display, along with how the art was displayed on the wall surfaces and the experience of how you interact with the art and the building, was well done.