The Nasher art collection is a must-see, as is the Renzo Piano building and the Peter Walker garden.
The Nashers developed the NorthPark shopping center in Dallas and have collected great art for decades. Now they are sharing it with the world. They have a number of permanent pieces installed outside in the garden, and space inside for permanent collection and rotating exhibitions.
The building was designed by architect Rienzo Piano, and it is constructed from stone and glass. The roof is glass, but has an interesting honeycomb shaped screen that lets only indirect lighting in.
It is located in the Arts District downtown, across from the Dallas Museum of Art (DMA). If you are staying Downtown, you can walk there from most hotels. If you are staying in Uptown, take the McKinney Ave. trolley downtown. It lets you off behind the DMA and the Nasher is just a block away to the east.