Jaitak Fort sits on a ridge about 15 km from Nahan, at around 1,500 metres. It was built in 1810 by the Gurkha general Ranjore Singh Thapa as a forward base during the Gurkha occupation of Sirmaur, and was contested in the Anglo-Nepalese War. The British eventually took it in 1815, and the loss formed part of the wider settlement that pushed the Gurkhas back into modern Nepal.
The fort itself is mostly ruined — fragments of stone walls and a few intact gates — but the ridge is the point. From the top you look across the entire Sirmaur valley to the Yamuna and on a clear day to the Doon Valley beyond. The walk up takes about an hour from the road head at Jamta village.