About Tiruchirappalli
Tiruchirappalli (formerly Trichinopoly in English), also called Trichy, is a major tier II city in the Indian state of Tamil Nadu and the administrative headquarters of Tiruchirappalli District. Trichy is the fourth largest city as well as the fourth largest urban agglomeration in the state.
According to Hindu mythology, Tiruchirappalli derives its name from the three-headed demon Trishira, who meditated on the Hindu god Shiva near the present-day city to obtain favours from the god. An alternative derivation, not universally accepted, is that the source of the city's name is the Sanskrit word "Trishirapuram"—Trishira, meaning "three-headed", and palli or puram meaning "city".
Source : Wikipedia