The race of chundan vallam ('snake boat', about 30-35 meter (100-120 feet) long with 64 or 128 paddlers aboard) is the major event. Hence Vallam Kali is also known as the snake boat race and is a major tourist attraction. Other types of boats which do participate in various events in the race are churulan vallam, iruttukuthy vallam, odi vallam, veppu vallam, vadakkanody vallam and kochu vallam. The Nehru Trophy Boat Race is a popular vallam kali event held in the Punnamada Lake near Alappuzha, Kerala, India.
In Kerala, during an early 13th-century war between the feudal kingdoms of Kayamkulam and Chembakassery, King Devanarayana of Chembakassery commissioned the construction of a war boat named Chundan Vallam and he tasked a famous carpenter of the day with the responsibility of creating it. Hence, the technical methods for creating these snake bats are around 650 years old. Of the snake boats still in use today, the Parthasarathi Chundan is the oldest model.
Vallam kali has mainly been conducted during the season of the harvest festival Onam in Autumn. The race of chundan vallam is the major event. Vallam kali also includes races of many other kinds of traditional paddled longboats of Kerala, and is one of the major tourist attractions in the state.
Vanchipattu (lit. 'boatsong') is the form of poetry in Malayalam language commonly used during vallam kali and related festivals. During Aranmula Uthrattadi Vallamkali, the vanchipattu is performed by the participants for its significance in the rituals. Ramapurathu Warrier is considered to be the pioneer of the vanchipattu.
List of periodical vallam kali events
Map of Backwaters in Kerala where boat racing is conducted