This april will mark 45 years since “Dallas”, a hit soap opera, first aired. The show, with its greedy oilmen, sun-soaked cattle ranches and lilting drawls, introduced the Lone Star State to the world. But it’s not just the big hair and grainy resolution that make “Dallas” seem dated today. It is also the Dallas skyline.

The opening credits showed a cluster of midsized office buildings, within sight of the open prairie. Since these shots were filmed, the skyline has soared and the city has sprawled. There is no open country for miles around. Instead, Dallas and nearby Fort Worth have merged into a “metroplex” of about 7.8m people. From 2010 to 2021 the population of this conurbation grew by 22%—triple the national rate and the fastest pace among America’s biggest cities. Its economy grew by 46% over the same period. Dallas-Fort Worth is expected to overtake greater Chicago as the country’s third-largest metropolis in the mid-2030s.