Dindigul Fort, TN can be made a popular tourist site if ASI takes care of encroachments and restoration!

Cannon on the Dindigul fort, TN en.wikipedia.org 

Cannon on the Dindigul fort, TN youtube.com

Above images:  A cannon  on the  Dindigul fort, TN: The cannons found Dindigul rock fort at vantage points are found to be of high quality  and have been free  from corrosion despite long age.  This being  due to the fact that the iron oxides present in the cannons are in the nano particle range.  The research study on these cannons  is confirmed by SEM and EDAX spectroscopy. 5 by the researchers..................... 

old image of Dindigul fort, TN  en.wikipedia.org 

After the short-lived Madurai Sultanate, in 1559 Madurai Nayaks,the vassal of  the Vijayanagara empire took full control over the region  and  Dindigul became a strategic gateway to their kingdom from North,   Strategically located in a  rocky terrain, the 17th century fort was originally built  by the Madurai Nayakar king Muthu Krishnappa Nayakar (son of Viswanatha nayak) in 1605. It is often called Dindigul fort or malai Kottai  and lies close to the Dindigul town. He also built a fort at the bottom of the hill and both Muthu Krishnappa Nayak and Thirumala nayak became successful rulers and during their reign this region prospered. 

Earlier Chola, Pallava and Chera rulers ruled this region at different period.  In the 18th century it was occupied by the kingdom of Mysore ( Venkata Raya ruled this place for the kingdom) and later, it came under the control of Hyder Ali ( who became de facto ruler of Mysore kingdom in 1777) and his son Tipu Sultan who was crowned as the ruler of Dindigul in 1788. This was done after a peace treaty with the British who captured this area. Again in the 2nd Anglo -Mysore war under Cap. James Stewart in a deal in 1792  Tipu ceded Dindigul and the fort to the British. 

In 1798 Dindigul is the first region to have come under English rule in the Madurai District and in the same year the British  army vastly improved the defense security of the hill fort strengthened the hill fort with several cannons and built  security   rooms in many places.  This region bears testimony to the valiant freedom fighters like  polygar of Virupachi, Gopal Nayak, the Sivaganga queen Queen Velu Nachiyar and her commanders Maruthu Pandiyar Brothers.  Hyder Ali was of great help to them during that period. 

After Tipu Sultan's death in the final Mysore Anglo war in 1799 at Srirangapatna , the British  consolidated their reign after their victory against the remaining Palayakarar. Till 1947, this region was with the British administered by the District Collector at Madurai. 

Dindigul fort, TN Dindigul fort, TN  dreamstime.com

 chambers with curved ceiling Dindigul fort, TN  localguidesconnect.com

With well cemented double walls to withstand heavy artillery fire the fort  is 900 ft (270 m) tall and has a circumference of 2.75 km (1.71 mi).  A  well planned fort with cannons installed  at vantage points, spy holes, etc.,  the fort also has double walled, well ventilated ammunition chambers with safety measures to face threats from enemies. An interesting feature is to prevent water seepage during heavy rains,  the ammunition godown and other chambers have sloping ceiling to drain out water quickly  and  to keep indoors safe from humidity. There is a circular freestanding bastion on the top at a strategic location on which several cannons were mounted. Artillery and cannons were introduced during the 17th century..  

chambers with curved ceilingdreamstime.com

Provided with a spacious kitchen, a horse stable and a meeting hall for the army commanders, there are 48 rooms/ in th ee fort. They were once served as cells  to lodge POW -  prisoners of war. The fort is a fine example of the 17th century fort architecture and they highlight the  ingenuity of the rulers.  They foresaw dangers and planned the design of the fort accordingly. Taking advantage of the steep gradient,  the planners had rainwater reservoirs constructed to survive long siege to the fort. 

Many parts of the fort like walls, arsenal depots, or animal stables) are poorly maintained by the ASI and visitors can access only selected areas. Atop the fort on the east side one can enjoy a nice vista of Dindigul city and the farm lands on the fringe areas. 

I have heard that the fort complex is undergoing major repairs and plans are afoot to  conserve the historical fort to promote tourism. 

https://en.wikipedia.org/wiki/Dindigul_Fort#Early_Dindigul_history

https://jchps.com/issues/Volume%209_Issue%201/jchps%209(1)%2037%20Rajendran%20166-168.pdf