One of the largest lakes in China, Hūlún Lake is called Dalai Nuur (Ocean Lake) in Mongolian. It unexpectedly pops out of the grasslands like an enormous inland sea. You can hire a horse (¥100 per 30 minutes) or a quad bike (¥100 per 20 minutes), take a boat ride (¥10 per 20 minutes) or simply stroll along the rocky lakeshore.
The only way to get to Hūlún Hú, 39km southeast of Mǎnzhōulǐ, is to hire a taxi. Expect to pay about ¥200 return, including a visit to the nearby Russian Doll Park.