THE DIFFERENCE BETWEEN Riyadh’s two principal neighborhoods is day and night. Literally.

Daytime Riyadh bakes in the desert heat, its modern skyline often blotted by heat haze, sand storms and pollution. From May to September, temperatures typically soar above 100 degrees Fahrenheit. Locals and visitors do their best to reduce their exposure to the vicious sun, taking refuge in air-conditioned buildings and traveling between them in air-conditioned vehicles.

After sunset, the temperature drops by 10 degrees or more, and a new city blossoms. Sidewalks and parks that, during the day, are sun-bleached and empty suddenly flood with people and color. The city lights up with neon and the sounds of families out strolling.

The World Sights Park just east of downtown, beside the Eastern Ring Road, proves a particularly charming place in which to mingle with locals. Here a trail leads you among spot-lit scaled replicas of famous international landmarks — the Taj Mahal, the Eiffel Tower, Egypt’s pyramids, Rome’s Coliseum — as well as a cluster of familiar Riyadh buildings.

Close by, the Saqer-Aljazirah Aviation Museum displays an excellent collection of aircraft and memorabilia spanning the entire history of aviation in Saudi Arabia. The exhibits are housed both indoors and in the surrounding gardens. Arrive in the hour before sundown to see the planes outside in the best light. The museum is open 4–8 p.m.

You don’t have to go far for a bite to eat. In the same locality, the Granada Center shopping mall features a large food court with a range of familiar American outlets as well as Saudi Arabian chains such as Shawarmer, which specializes in kebabs.

Riyadh, a huge, sprawling city of more than 7 million people, is made up of a patchwork of neighborhoods, some commercial and exceptionally modern, some retaining fragments of the city’s past, some exclusively residential. In the course of your visit, as the city’s geography falls into place and you become familiar with some of these districts, you soon understand the crucial demarcation is not geographic. Riyadh’s best neighborhood is the night.