Cúc Phương National Park  is located in Ninh Bình Province, in Vietnam's Red River Delta. Cuc Phuong was Vietnam's first national park and is the country's largest nature reserve. The park is one of the most important sites for biodiversity in VietnamCúc Phương is situated in the foothills of the northern Annamite Range. The park consists of verdant karst mountains and lush valleys. Elevation varies from 150 meters (500 feet) to 656 m (2,152 feet) at the summit of May Bac Mountain, or Silver Cloud Mountain. The limestone mountains house numerous caves, many of which are accessible for exploration.The average temperature in Cúc Phương is 21 Celsius (70 Fahrenheit), with a mean winter temperature of 9C (48F). High temperatures can reach above 30C (85 F) and lows are just above zero (32 F). At the low elevations in the valley the temperature is hot and humid while at higher elevations the temperature drops and frostbite is a threat. On average it rains more than 200 days a year and the average annual rainfall is 2,100mm (7 feet). The dry season is November to February, the driest months being December and January.