Kerala is an established destination for both domestic as well as foreign tourists. Kerala is well known for its beaches, backwaters in Alappuzha and Kollam, mountain ranges and wildlife sanctuaries. Other popular attractions in the state include the beaches at Kovalam, Varkala, Kollam and Kappad; backwater tourism and lake resorts around Ashtamudi Lake, Kollam; hill stations and resorts at Munnar, Wayanad, Nelliampathi, Vagamon and Ponmudi; and national parks and wildlife sanctuaries at Periyar, Parambikulam and Eravikulam National Park. The "backwaters" region—an extensive network of interlocking rivers, lakes, and canals that centre on Ashtamudi Lake, Kollam, also see heavy tourist traffic. Heritage sites, such as the Padmanabhapuram Palace, Hill Palace, and Mattancherry Palace, are also visited. The city of Kochi ranks first in the total number of international and domestic tourists in Kerala. To further promote tourism in Kerala, the Grand Kerala Shopping Festival was started by the Government of Kerala in 2007. Since then it has been held every year during the December–January period.