The Bob Bullock Museum is the best single introduction to Texas history in the state. Three floors of exhibits trace the full arc of Texas's past: the indigenous peoples of the region, the Spanish colonial period, the Republic of Texas, the Civil War and Reconstruction, and the 20th-century story of oil, ranching, and the modern tech economy.
The building itself is impressive — a great rotunda with a dramatic entrance sculpture — and the exhibits are genuinely engaging rather than merely comprehensive. The star-shaped mosaic floor in the ground level entrance is a Texas classic. The museum also has an IMAX theatre showing Texas-themed films. Worth two to three hours; the upper floor exhibits on 20th-century Texas are particularly strong.