You must have seen ruins of this ancient temple in Haidar's Bismil song and did you wonder? This is Martand Sun Temple of Anantnag. It is one of the only two Sun Temples in India, the other being in Konark, Odisha. The temple was built by King Lalitaditya Muktapida around 725-756 AD. The temple was completely destroyed by Sikandar Butshikan in early 15th century. It took one year for Sikander Butshikan to fully damage and destroy it.
You can search google on this topic; Historians account: During his rule Hindus were forcibly converted to Islam and were massacred in case they refused to be converted. And Sikandarpora (a city laid out by Sultan Sikandar) was laid out on the debris of the destroyed temples of the Hindus. In the neighbourhood of the royal palaces in Sikandarpora, the Sultan destroyed the temples of Maha-Shri built by Praversena and another by Tarapida. The material from these was used for constructing a 'Jami' mosque in the middle of the city. Towards the fag end of his life, he (Sultan Sikandar) was infused with a zeal for demolishing idol-houses, destroying the temples and idols of the infidels. He destroyed the massive temple at Beejbehara. He had designs to destroy all the temples and put an end to the entire community of infidels.
In his second Rajtarangini, the historian Jonraj has recorded, "There was no city, no town, no village, no wood, where the temples of the gods were unbroken. When Sureshavari, varaha and others were broken, the world trembled, but not so the mind of the wicked king. He forgot his kingly duties and took delight day and night in breaking images."