Fair Park is what Dallas built for the 1936 Texas Centennial and then, unusually, kept. It is 277 acres of art deco — the largest intact collection of it anywhere in the world — arranged around a long reflecting pool called the Esplanade.
What makes it useful for a group is that it is not one attraction. It is several, sharing a car park. The Texas Discovery Gardens has a butterfly house where the butterflies land on people. The African American Museum of Dallas is free and rarely crowded. The Cotton Bowl sits at the far end. If your group splits on what it wants to do, this is the place where that stops being a problem.
Go in spring or autumn. The grounds are wide open with little shade, and a July afternoon here is genuinely hard work with young children. Individual museums keep their own hours, so check two before you set off rather than arriving to find both shut on a Monday.
If your dates fall in late September or October, the State Fair of Texas takes over the whole site. Wonderful, and completely different — expect crowds, queues and a fried food menu that has to be seen.
