During British rule, Tiruchirappalli was known for its tanneries, cigar-manufacturing units and oil presses. At its peak, over 12 million cigars were manufactured and exported annually. Tanned hides and skins from Tiruchirappalli were exported to the United Kingdom. The city has a number of retail and wholesale markets, the most famous among them being the Gandhi market which is an important source of vegetables for the whole region. Other notable markets in the city are the flower bazaar in Srirangam and the mango market at Mambazha Salai. The suburb of Manachanallur is known for rice mills where polished Ponni rice is produced.
A weapon manufacturing unit, Ordnance Factory Tiruchirappalli manufactures products like grenade launchers, multi shell launchers, rifles for the Indian Armed Forces and a Heavy Alloy Penetrator Project (HAPP) facility are run by the Ordnance Factories Board of the Government of India. The HAPP unit, set up in the late 1980s, comprises a Flexible manufacturing system (FMS), the first of its kind in India. Tiruchirappalli is a major engineering equipment manufacturing hub in Tamil Nadu. The Golden Rock Locomotive Workshops, moved to Tiruchirappalli from Nagapattinam in 1928, is one of the three railway locomotive manufacturing units in Tamil Nadu. The workshops produced 650 conventional and low-container flat wagons during the year 2007–2008. The chief workshop manager's office at Golden Rock was awarded a star rating by the Bureau of Energy Efficiency for the proper and regulated usage of electricity in its offices.
A High Pressure Boiler manufacturing plant was set up by the Bharat Heavy Electricals Limited (BHEL), India's largest public sector engineering company, in May 1965. This was followed by a Seamless Steel Plant set up at a cost of 58 crore (US$13 million) and a Boiler Auxiliaries Plant. The three manufacturing units constitute the BHEL industrial complex and cover a total area of about 22,927.4 square
