The O'Donnell Heritage Museum showcases local history in this town that was home to the family of actor Dan Blocker, who portrayed Hoss Cartwright on TV's Bonanza. Though born in DeKalb in East Texas, Blocker was reared in O'Donnell, and the museum includes exhibits related to his life and career.

The museum is housed in a 1925 two-story bank building that remains in its original condition. Permanent exhibits illustrate life in late 19th-century to 20th-century West Texas: the telephone system, a reed organ, bedroom furniture, kitchen equipment, blacksmith shop, schoolroom, post office, legal and doctor offices, a formal parlor, and a restored church congregation at worship.

O'Donnell, located 45 miles south of Lubbock, was established in 1910 as a stop on the Panhandle and Santa Fe Railroad, a subsidiary of the Atchison, Topeka and Santa Fe, and is named for rail promoter Tom J. O'Donnell. In 1911 L. G. Phillips opened the first business in O'Donnell, the first fully automatic cotton gin in North America.

Across from the museum is the old Blocker store, no longer in operation but featuring a hand-painted "Hoss" hat on the side of the building. The nearby lot contains sculptor Glenna Goodacre's bust of Blocker, which was dedicated on July 4, 1973, a year after his death.