People don't know there is an Original Story behind Old Belgaum. But this story below will clarify your doubts.

It is hard to believe, but the truth was written long back with evidences by a British writer GILMOUR M’CORKELL in his book THE INDIAN ANTIQUARY.

He clearly tells that there were 108 Jain Temples in the premises of the present Belgaum Fort, which were demolished and overthrew by the then Musalman kings and ultimately with the same stone and pillars the Belgaum Fort as built.

He also clearly mentions in the Book:

but the earliest notice that we have of it is to be found in the Gulhalli inscription 1150 AD."
[ Reference Book A Legend of Old Belgaum, May 1875 Pg - 139 ].

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The Legend

There was a poet by name Sarasijabhavanandana, belonging to the ancient Jaina cast, and an inhabitant of Belgaum. He has composed in Old Kanarese language a short history of kings. Having, by means of rhetorical and an ornate Sanskrit expressions, applied such epithets as ripen as if they were plentiful given in the Karnataka Country, he has complied an account of Belgaum. In it we obtain full information of those kings who formerly were, their names, their good qualities, their castes, and the virtuous deeds that they preformed. And memorials of the acts which were done by those same kings are to be met with, even in the present day, in Belgaum, and are as written below :-

Sapur and Belgaum were formerly collectively called Jirnasitapura, and there lived there governor of the city of Samantapattana, whose name was Kuntamaraya, a Jaina by caste, very religious and compassionate. So the people had great joy and happiness. One day (it happened that) one hundred and eight Jaina sages, -- who had come from the South Country into the forest of Anagola, of which the name was formerly Hrasvagiri -- remained there all night, because their rules did not permit them to advance a single footstep during the darkness. When this news reached Kuntamaraya, the King, with the expressed assent of his wife Gunavati, went out to the sages and, having preformed respectful obeisance, besought them as follows :- “ Oh mighty saints, take pity upon me and bestow your favour upon me, so that my region may become famous.” But, as their custom was never to say anything at night, they held no converse with the king. Accordingly the king returned home in great despondency, (and, as he was going) sparks of fire fell from the torches, and the dry forest was set on fire, and all those sages were burnt to ashes.

On the following day, in the early morning the king again went into the forest and saw all those Jaina sages had been consumed. When they saw this, both husband and wife were much terrified and began to consider. Accordingly there and then, he proposed a plan to Gunavati, where by these Jaina sages might attain the state of final emancipation, -- as follows: - “Let us bring stones and build 108 temples, and, when we have performed worship to them, I shall accomplish the propagation of offspring.” When he has so said, they returned home, and, and in accordance with the above plan, he caused to build 108 Jaina temples at that very place where are even at the present day some Jaina Temples in the Fort of Belgaum. After he had initiated into the mysteries of the Jaina faith and had reigned for some time, Gunavati at length became pregnant. And now, although he had been very anxious that his wife should have children, his dread of not having any offspring vanished. On this account he gave to Belgaum the name of Vamsapura. Now the word in Marathi for Vamsa is Bel. In this manner we arrive at the name Belgaum.

Afterwards they lived in Old Belgaum, Santa the son of Kuntam the king of Savantavadi, famous, deeply learned in the mysterious of the Jaina religion, thoroughly skilled in the worship of the gods of forefather, very brave, and lauded by prince who are born in the races of the Sun and Moon, a supporter of the rules of the faith of the Kshatriyas, a protector of Jaina sages, very skilful in bestowing on the temples of Jinendra that wealth which consists in courtesans, &c. He had fourteen wives. The chief of there wives, by name Padmavati, was very famous. She had a son by Santa named Anantavirya. One day, attended by his retinue of maid-servants, &c. he (Santa) went to the river Sundarsana near Yalur for the purpose of playing in the water, and in the lake of Nagasarovara he met his death by a thunderbolt. Then three ministers of state came from Savantavadi and crowned Anantavirya King. He also reigned according to the customs of his fathers. One day, many sages, along whom Sudarsana was the chief, arrived. When he has made respectful obeisance to them, Anantavirya inquired concerning his ancestors, and those sages recounted from their Puranas the above story in which has been related to fate of King Santa.

Afterwards there was a king of his race and lineage by name Mallikarjuna. During his reign a famous Musalman by name Asta Khan (Asad Khan) came from Bengal, and, Asta Khan acquired the kingdom of treachery, he deposed him (Mallikarjuna), overthrew those one hundred and eight Jaina temples, and built a fort. Even at the present time we find stones (belonging to those in the fort).

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