Popular attractions in Kerala include the beaches at Kovalam,Cherai and Varkala; backwater tourism and lake resorts around Vembanad Lake, Kumarakom and Alapuzha; hill stations and resorts at Munnar, Wayanad, Nelliampathi, Vagamon and Ponmudi; and national parks and wildlife sanctuaries at Periyar and Eravikulam National Park. The "backwaters" region ia an extensive network of interlocking rivers, lakes, and canals that centre on Alleppey, Kumarakom, and Punnamada also see heavy tourist traffic. Heritage sites, such as the Padmanabhapuram Palace, Hill Palace, Mattancherry Palace are also visited.