Kerala's Backwater is the backbone of  tourism in Kerala. The Kerla backwaters which dates back over the centuries had been long used for all transportation needs and stretches over 1900 km.The most interesting area in the backwaters tourism is the Kuttanad region, called the rice bowl of Kerala.The largest backwater stretch is the Vembanad Lake, which opens out into the sea at the Cochin port and flows through the three districts-Alappuzha (Alleppey), Kottayam and Kochi. The Ashtamudi Lake has eight 'arms' covering a major portion of Kollam(formerly Quilon) district in the south, and is the second largest lake in the state. The major attraction of backwater tourism in Kerala is the houseboat trip, which adds extra thrill and excitement. The backwaters in Kerala plays a major role in the Kerala Tourism industry. It has become one of the 50 must see places in the world. Enjoying a cruise in these backwaters is not to be missed, as it leaves you feeling fully rejenuvated.The best way of experiencing the beauty of the backwaters in kerala is to cruise along either in a rented boat, a canoe or in Houseboats which are specifically for tourists.The houseboats, or Kettuvalloms as they are natively called, are giant boats measuring around 80 feet in length. They are constructed by tying wooden planks together with ropes made of coir(coconut husk) without using a single nail.