Old tradition tells that the name Thiruvalla / Tiruvalla comes from the word “Valla Vaay”, named after the river Manimala which was known as Vallayār in ancient times. Before roads were developed, Thiruvalla village developed at the mouth of river Vallayar, connected far and near places through waterways, hence known as Valla vāi(vāy in old Malayalam means mouth of river). Later the Thamizh Prefix ‘Thiru (means holy /revered) attached to it and became Thiruvalla.
Thiruvalla lies at an altitude of 9 m above sea level, on the basin of the rivers Pamba and Manimala. Thiruvalla is dotted with several natural canal streams (called “thodu” in Malayalam) like Chanthathodu, Manippuzha, Mullelithodu, and several others. The city area has riverine alluvial soil, and eastern parts have a laterite loam kind of soil classified under “Southern Midlands” agro-ecological zone, while the western suburbs like Niranam have a more sandy type of soil that resembles beaches. (Kuttanad agro-ecological zone) The reason for this is believed to be the older status of Niranam as a port, before reclamation of Kuttanad from sea occurred. The Upper Kuttanad region in Thiruvalla has the “Karappadam” type of soil, which is clay loam in texture, has high organic matter, and is situated in areas about 1–2 m above sea level.
The climate of Tiruvalla is classified as tropical. There is significant rainfall in most months of the year. The short dry season has little effect on the overall climate. The temperature here averages 27.3 °C. In a year, the average rainfall is 3298 mm.
Due to proximity to the equator, Tiruvalla has very little variation in average temperature. During the year, the average temperatures vary by 2.6 °C.
Tiruvalla is best known for its pleasant and welcoming weather. South West Monsoon winds bring heavy showers to Tiruvalla in the months of August for a couple of months. Tiruvalla has a distinctively tropical, yet pleasing climate. The best time to visit this historical town is after the rains as the healthy showers of monsoon leave this place lush green and pristine.
The city inside the modern municipal limits has an almost equal number of Christians (48.03%) and Hindus (46.92%). Muslims form 4.80% of the population.
Majority of the Christians in Tiruvalla belongs to Malankara Marthoma Syrian Church, Indian Orthodox and India Pentecostal Church of God.
Tiruvalla is home to the Sree Vallabha Temple which is the only one of its kind in the State to have Kathakali performed as a ritual offering every night.
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