A small hill station at about 1,100 metres in the Eastern Ghats, Yelagiri is a cluster of 14 villages among orchards, rose gardens and forest. A road with 14 hairpin bends climbs up from the plains at Ponneri. It is quieter and far less built up than the better-known hill stations, and its trekking trails, paragliding and adventure camps make it a popular weekend escape from Chennai and Bengaluru.

The centre of life in Yelagiri, this man-made lake has pedal and rowing boats, a park with a musical fountain and paths around the water. Hills dotted with eucalyptus and fruit trees ring it, and it is busy at weekends with families from Chennai and Bengaluru, but early mornings on the water are calm and cool.

Set in the Javadi hills at Kavalur, the Vainu Bappu Observatory houses one of the largest optical telescopes in Asia, the 2.34-metre Vainu Bappu Telescope, commissioned in 1986. Observations from Kavalur helped detect the rings of Uranus in 1977. The observatory opens to the public on Saturday evenings, when visitors can see the main domes and look through a smaller telescope at the night sky.

Delhi Gate is the surviving northern gateway of the fort of Arcot, capital of the Nawabs of the Carnatic from the early 18th century and the prize in the long struggle between the French and English East India Companies. The fort is remembered above all for the siege of 1751, when Robert Clive held it for fifty days with a small garrison against a far larger force. Little else of the fort is left; the gate stands near the Palar river with an old mosque and tanks beside it.

Sholinghur, known in Tamil tradition as Thirukkadigai, is a Divya Desam where Yoga Narasimha is worshipped on the larger of two rocky hills, reached by about 1,300 steps, with a shrine to Yoga Anjaneya on the smaller hill facing it. The name Kadigachalam comes from the belief that prayer here is answered within a kadigai, a span of roughly twenty-four minutes. The Alvar Tirumangai sang of the place, and inscriptions record endowments by the Cholas and the Vijayanagara rulers. In September 1781 a British force camped below this rock before the battle of Sholinghur against Hyder Ali.

This rock-cut shrine was cut into a granite boulder in the early 7th century under the Pallava king Mahendravarman I, whose inscription here names the temple Mahendra-Vishnu-griham and the village after himself. It is among the earliest Pallava cave temples and one of the few of its period dedicated to Vishnu rather than Siva. The inscription is an important record of the beginning of rock-cut architecture in the Tamil country.