Trichy encompasses Srirangam, a Vaishnavite temple and the biggest functioning Hindu temple in the world. Trichy also emcompasses "ThiruAnaikka" (ThiruvAnaikkaval), one of the five main abodes ("Panchaboodha Sthalam") of Lord Shiva. ThiruvAnaikkaval is the House of Water. Chandrasekhara Venkata Raman was born in Thiruvanaikaval and his house has been preserved as a museum. There Tiruchirapalli city was named after a three headed demon "Trishira" ] called "Chira"(the son of Ravana) who performed penance at the Siva temple here and obtained boons.Legend has it that Shiva was worshipped by the demon ruler Tirisiran, hence Tiruchirappalli, Tirisirapuram etc. Also, since the three peaks here on this hill are occupied by Shiva, Parvati and Vinayaka, the name Tri-Shikharam or Tirisirapuram came into being. Legend has it that Shiva in the guise of a woman (mother) attended to the call of a devotee in labor, hence he is called as Matrubhuteswarar.
There is yet another belief about the origins of the name Trichy. Apparently the name started out as Thiru Javvandhipuram (Place of Marigold flowers; javvandhi, the Tamil name for the flower Marigold which grew(and still does) in abundance in and around this region and the word puram refers to a place of dwelling) which over time became corrupted to Trichy.