Kolar district is a district in the state of Karnataka, India. Kolar is the district headquarters. Located in southern Karnataka, it is the state's easternmost district. The district is surrounded by the Bangalore Rural district on the west, Chikballapur district on the north, the Chittoor district of Andhra Pradesh on the east and the Krishnagiri and Vellore districts of Tamil Nadu on the south.
On 10 September 2007, it was bifurcated to form the new district of Chikballapur. Due to the discovery of the Kolar Gold Fields, the district has become known as the "Golden Land" of India.
Kolar was called Kolahalapura during the Middle Ages, but later came to be known as Kolar. It was the battlefield for the warring kingdoms of Chalukyas in the north and Cholas to the south. It was the capital of the Gangas until 4th century AD when they shifted the capital to Talakad in Mysore. In 1004 AD, the Cholas annexed Kolar until 1116 AD,. Vishnuvardhana (1108-1142 AD) freed Gangavadi from the Cholas, and in commemoration of his victory, built the celebrated Vijayanarayana Temple (Chennakesava Temple) at Belur. The major and important temples in the town are Kolaramma Temple and Someshwara Temple. The Kolaramma temple is of Dravida Vimana style built in Ganga tradition in the 2nd century CE and dedicated to goddess Shakti. The temple was later renovated during the period of the Chola monarch Rajendra Chola I in the 10th century and Vijayanagara kings in the 15th century.Someswara Temple is a fine example of 14th century Vijayanagara art.