Yunnan Province Grain and Oil Wholesale Trading Market. Yunnan Province is located in southwest China. The Yunnan Grain and Oil Wholesale Trading Market is located on Yunshan Road, Xishan District, Kunming City, Yunnan Province. It is the largest rice wholesale market in Yunnan. The largest rice wholesale market in Kunming is the Yunnan Grain and Oil Wholesale Trading Market. Kunming, also known as Spring City, is a prefecture-level city, provincial capital, megacity, and central city of the central Yunnan urban agglomeration under the jurisdiction of Yunnan Province.