Thrissur Pooram in the context of Temple festivals of Kerala

Thrissur (Malayalam: തൃശൂർ, pronounced [triˈʃ(ː)uːr] ), formerly Trichur, also known by its historical name Thrissivaperur, is a city and the headquarters of the Thrissur district in Kerala, India. It is the third largest urban agglomeration in Kerala after Kochi and Kozhikode, and the 21st largest in India. Thrissur is classified as a Tier-2 city by the Government of India. The city is built around a 65-acre (26 ha) hillock called Thekkinkadu Maidanam which seats the Vadakkumnathan temple. It is located 284 kilometres (176 mi) north-west of the state's capital city, Thiruvananthapuram. Thrissur was once the capital of the Kingdom of Cochin, and was a point of contact for the Assyrians, Greeks, Persians, Arabs, Romans, Portuguese, Dutch and English.

Thrissur is known as City of Celebrations and also called the cultural capital of Kerala because of its cultural, spiritual and religious leanings throughout history. The city centre contains the Kerala Sangeetha Nadaka Academy, Kerala Lalithakala Akademi and Kerala Sahitya Academy. The city hosts the Thrissur Pooram festival, the most colourful and spectacular temple festival in Kerala. The festival is held at the Thekkinkadu Maidan of Vadakumnathan Temple in April or May, in the Malayalam month 'medam'.

Thekkinkadu Maidanam is a historic open ground located in the center of Thrissur city in the Kerala state of India. The 65-acre area surrounds the ancient Vadakkunnathan Temple, one of the most significant Shiva temples in Kerala, and is a vital cultural and historical landmark. The maidan is under the management of the Cochin Devaswom Board and plays host to a variety of public events, including the famous Thrissur Pooram, one of the largest temple festivals in Kerala, often referred to as the "Mother of all Poorams."

The Vadakkumnathan Temple is an ancient Hindu temple dedicated to Shiva in Thrissur, in the Thrissur district of Kerala, India. The temple is a classical example of the architectural style of Kerala and has one monumental tower on each of the four sides in addition to a koothambalam. Mural paintings depicting various scenes from the Mahabharata can be seen inside the temple. The shrines and the Kuttambalam display vignettes carved in wood. The temple, along with the mural paintings, has been declared as a National Monument by India under the AMASR Act. According to popular local lore, this is the first temple built by Parashurama, the sixth avatar of Vishnu. Thekkinkadu Maidan, encircling the Vadakkumnathan Temple, is the main venue of the renowned Thrissur Pooram festival.

In 2012, the Archaeological Survey of India (ASI) has recommended 14 sites, including Vadakkumnathan Temple and palaces, from Kerala to include in the list of UNESCO World Heritage Sites. The temple is also the first one among the 108 Shiva Temples in ancient Kerala, established by Parashurama, and is mentioned in the Shiva Temple Stotra as Shrimad-Dakshina Kailasam, meaning 'Mt. Kailash of the South'.