Aranmula, in Pathanamthitta district, is famous as one of the five temple towns like Guruvayur. Other major temples associated with the worship of Lord Krishna are those of Trichambaram, Tiruvarppu and Ambalappuzha. Lord Parthasarathy is the presiding deity of the Aranmula temple. There are five ancient shrines around Chengannur, sanctified by the Pandavas. They are at Aranmula (Arjuna), Chengannur (Yuddhishtra), Tiruppuliyur (Bheema), Tiruvanmandur (Nakula) and Tirukkadittaanam (Sahadeva). The Tamil hymns of Nammalwar of the 1st millennium CE glorify this legend.

Apart from the beautiful mirror made out of polished bell metal, familiarly known as Aranmula Kannadi, this village is well known for Aranmulayuttu, a feast given for children, as an offering to the deity of Aranmula, Uthrattathi boat race, Thiruvona sadya (an elaborate feast after the water carnival). Varuttha erusseri distributed at this very famous Valla sadya is a special curry for this feast with sixty various items. The variety of condiments has made it a very costly one. In the month of Chingam, of the boat races held on five days starting with Tiruvonam, the most famous is the one held on Uthrattathi day. The other famous vallam kali is the one held in this temple on Ashtami Rohini day.

According to legend, Arjuna built this temple at Nilackal near Sabarimalai. Later the image was brought to Aranmula on a raft made out of six (aaru) bamboos (mula) and the name of the village came to be known as Aranmula. Arjuna was believed to have installed the image of Krishna, as Parthasarathy.

Legend says that a Brahmin devotee, as per a vision of Krishna, offered 51 measures of rice to the Aranmula temple, carried in a boat. On one such occasion, the rival men from another village intercepted this boat. But the snake boats of this village raced to his rescue. In commemoration of this event a boat race is held along the tropical river Pampa, every August.

A snake boat, in the service of the temple is known as palliyodam, which means the boat that belongs to the Lord. In the beginning, on the main day of the festival, 48 palliyodam of the 48 karas, from Chennithala in the west to Ranni in the east, participated in the festival. Now this has been reduced to thirty-two snake boats representing 32 villages. Adorned elaborately with decorations, the boats are manoeuvered in such a way as to view the Parthasarathy temple, on the banks of the Pampa. The oarsmen, wearing white dhotis and covering heads with scarfs, row the boats in rhythm to the tunes of hymns composed for the purpose.

Boats are built with the liberal donation of the devotees, in accordance with the specifications laid down in ancient scripture on odam/ wooden boat building. It takes 650 man-days to build a single snake boat. The hull made out of wooden planks is 83 feet in length and six inches thick. This 150 feet long boat can hold 100 men. The head and tail are constructed in such a way as to project out five and three feet, respectively, above the water. The boat provides seating compartments on a raised platform for 64 oarsmen who represent 64 art forms. Four master oarsmen, who symbolize the four Vedas, control the direction of the boat with large oars. The platform in the middle of the boat facilitates eight people to stand. They represent the Ashtadikpalakas (devas), who guard the eight directions.

During Onam boat races are held at Ernakulam, Kottayam and Champakulm (Changanasseri). The boat race held at Alleppey every year on the second Saturday in August is to commemorate Pandit Jawaharlal Nehru's visit to that town in 1952. But the boat race held at Aranmula is hailed as the most spectacular. The chundan vallams (Snake Boats) built for Onam boat race are taken to the water only during the Onam festival. A village owned the boats and kept them in special sheds. The villages compete with each other to own bigger and better boats, needed to win the race. The highly ornate tall stern like the Viking boats, that rises six to eight feet above the water, is gracefully carved and elaborately decorated with shining brass ornaments and silken multicolored tasseled umbrellas. There may be more than twenty boats taking part in the regatta. Of them, some boats will be more than 50 feet long and 6 feet wide.
More than 100 experienced oarsmen in decorative garbs propel the boat to the beat of drums and songs. The unified action of sixteen feet long oars at the helm to rudder the boat, from a height of eight feet above the water, is decisive to win the race. The raising and dipping of the oars in unison, gives to the onlooker a thrilling sight of a bird in flight.

Lyrics known as vanchippattu (Song of the boatmen) are sung in tune with the traditional percussion instruments aimed at keeping up the spirits of the boatsmen. They have devotional, mythological or rustic themes. Every snake boat has about twenty-five singers and the rhythm of their songs is perfectly blended with the movement of the oars. The mariner’s song (kappal paattu) is a kind of philosophic song.

The front portion of a snake boat is known as vetithadi. A windscreen known as kaattumara, is a place where wind can hardly enter. Snake boat has made use of this wind proof platform for the singers and instrumentalists to stand there.
The stern of a vessel, or the helm is called Amaram. The helmsman who steers the boat is the Amarakkaran. The curl at its stern (helm) represents the raised hood of a snake. The boat with a height from the water level at the rear, a width of six feet, a length of about 60-65 meters and the curl at the stern qualifies the boat to be called a snake boat, and its carrying capacity is hundred plus during the race time. The majestically caparisoned stern that is decorated with a flag and elaborate shining brass ornaments. The entire length of the boat is arrayed with silken multi-coloured ornate parasols. With 95 paddlers, 5 helmsmen and 10 nilakkar it resembles a snake, while on the move. The role of nilakkar is to enhance the vigour and enthusiasm of the paddlers.

Chundan vallams, also called snake boats, were originally designed as a naval vessel and served as the traditional battle vessels of the Maharajas. A tubular vessel in which the boatmen preserve condiments, spices etc is kumpam. Veppuvallam is valiya vallam. There is a boat by name veppu/ Vaippu vallam. Veppu pura is the place where cooking is done. Provision for cooking in this boat won it the name veppu vallam. Its passenger capacity is about 40-45 persons. Its one end is higher than the level of the other end. These boats were designed as catering vessels to accompany battle vessels in olden times.

The boats in Kerala owe their name to their shapes, sizes or purposes. Prow is a nautical word that denotes the front part of a ship's hull, the bow. Owing to the curl at the stern, the boat earned its name chundan vallam. It is both a passenger boat as well as a kind of race boat. Its carrying capacity is about 45 persons. Ornamental carvings in coils at the prow and stern of the country boats are known as churul. This curled or coiled carving at its prow and stern earned it the name churulan vallam. Churulan, along with cheruchundan, parunthuvalan, odi vallam and chundan vallom, also belongs to the kaliyodam, kali vallom, kali vanchi category of race boats used for the vallom kali, one among the sports of the village folk in Kerala.