Answer: Yes, foreigners can generally travel freely from Xining to Zhangye on their own, especially if you are taking regular public transport like trains or buses. Both Xining and Zhangye are open to domestic and international travelers, and there are no special permits required for the areas you plan to visit in Qinghai and Gansu provinces, as long as you stay on standard tourist routes.

Answer: Hiring a private driver from Xining for a 2-day trip to Qinghai Lake and Chaka Salt Flats is a common and practical option, especially for a group of 4 passengers. These attractions are located quite far from Xining, and public transport options are limited for flexible sightseeing, so a private car and driver ensures convenience and allows you to travel at your own pace.

Answer: Your plan for a day trip around Xining is quite sensible. Both Ta’er Monastery and Riyue Mountain are relatively close to Xining, making them ideal for a relaxed day trip without long travel times. Qinghai Lake, as you mentioned, is much farther (around 150 km / 3 hours one way), so visiting it in a single day trip would be rushed and tiring.

Answer: Given that you only have 2 full days in Qinghai, trying to cover Kumbun Monastery, Qinghai Lake, and Chaka Lake is indeed very ambitious. The distances and travel times are significant: Xining to Kumbun Monastery is around 2-3 hours one way, Xining to Qinghai Lake is about 3-4 hours, and Chaka Salt Lake is roughly 4-5 hours from Xining. Adding in return trips and sightseeing time makes it very tight to fit all three destinations comfortably.