Ürümqi is not a typical tourist city, and that is partly what makes it interesting. It sits at the crossroads of the old Silk Road, and the traces of that heritage — Uyghur, Kazakh, Han, and a dozen smaller peoples — are woven through the city's markets, food, and streets. The main sights cluster in a manageable central area, with the grand exception of Tianchi (Heavenly Lake), which deserves a full day trip out into the Tian Shan.
The Xinjiang Museum is the single best reason to plan a stop in Ürümqi: its collection of Tarim Basin mummies is extraordinary and unlike anything you will find elsewhere. The Xinjiang International Grand Bazaar in the Erdaoqiao district is the beating heart of Uyghur commercial life in the city — dried fruit, spices, carpets, and handmade knives fill stall after stall. Red Mountain (Hongshan) offers an easy climb and the best panorama over the city's sprawl. And if you have a full day to spare, Tianchi — the alpine lake 115 km east of the city — is one of the most beautiful landscapes in Central Asia.
Be aware that Xinjiang has been under intensive security measures since 2017. Checkpoints are common, phone searches happen, and face-recognition cameras are everywhere. Travel is possible and the city functions normally for visitors, but the atmosphere is unlike anywhere else in China. Understanding that context adds depth to what you see here, rather than detracting from it.