Hassan is a district in Karnataka state, India. The district headquarters are Hassan.

Hassan district was the seat of the Hoysala Empire which at its peak ruled large parts of south India from Belur as its early capital and Halebidu as its later capital during the period 1000 – 1334 CE.

The place is called Hassan after the Goddess “Haasanamba”, the goddess and presiding deity of the town. The history of Hassan district is essentially the history of two of the well known dynasties that have ruled Karnataka, the Western Ganga Dynasty of Talkad (350 – 999 CE) and the Hoysala Empire (1000 – 1334 CE). In the 15th and 16th centuries, the Vijayanagar kings patronised Chennakesava of Belur as their family deity. It was also ruled by Adilshahis of Bijapur and Mughal Empire after decline of the Vijayanagar. In the 17th and 18th centuries, Hassan became a land of contention between the Keladi Nayakas of Shimoga and the Mysore Kingdom. It finally merged as an independent Mysore kingdom.

Around 300 BCE Hassan was part of the Mauryan empire. Sage Bhadrabahu arrived from north India in the 3rd century BCE along with many ascetics marking the arrival of Jainism into Karnataka.

Hassan Airport is expected to be operational by 2018 and is expected cater to a passenger capacity of 3 million and cargo capacity of 100,000 ton yearly. The airport will be an aircraft maintenance and modification (AMM) hub

The Karnataka State Road Transport Corporation operates connecting Hassan with other parts of Karnataka as well as other states. Hassan is connected by road via national highway No. 75 to the rest of the country.

Hassan comes under the South Western Railway zone of the Indian Railways. Hassan City Railway station connects it to the rest of the country through the Indian Railways.

Tropical savanna climates have monthly mean temperature above 18 °C (64 °F) in every month of the year and typically a pronounced dry season, with the driest month having precipitation less than 60mm (2.36 in) of precipitation. The Köppen Climate Classification subtype for this climate is “Aw” (Tropical Savanna Climate).

Lying between 12° 13´ and 13° 33´ North latitudes and 75° 33´ and 76°38´ East longitude, Hassan district has a total area of 6826.15 km². The geography is mixed with the malnad or mountainous region to the west and south west called Bisle Ghat and the maidan or plains regions in the north, south and east. There are some areas of degraded forest ranges in central portion of the district.

The district is surrounded by Chikmagalur District to the north west, Chitradurga District to the north, Tumkur District to the east, Mandya District to the south east, Mysore to the south, Kodagu District to the south west and Dakshina Kannada district to the west.

Hassan and Belur stand around 3,084 feet (940 m) and 3,150 feet (960 m) above sea level, respectively.

Most of the district lies in the watershed of the Hemavathi River, a tributary of the Kaveri River. The general level of Hassan district slopes with the course of the Hemavati, from the peaks of the Western Ghats downwards to the southeast. The chief tributary of the Hemavathi is the Yagachi River, which flows southward from Belur taluk to join the Hemavathi near Gorur. In 1981 the Hemavathi Dam was completed near Gorur, downstream from the confluence with the Yagachi, creating a reservoir of 8000 hectares. The Hemavathi passes through Holenarsipur taluk in a southerly direction and joins with the Kaveri near Hampapura in Mysore district, close to the border of Hassan district. The Kaveri flows through the southernmost part of the District.

Hassan District is administratively divided into eight talukas (Panchayat blocks): Alur, Arkalgud, Arsikere, Belur, Channarayapatna, Hassan, Holenarasipura (H.N. Pura) and Sakleshpur,[6] and 258 panchayat villages.