Jammu and Kashmir.

This monumental map of Jammu & Kashmir is nothing short of an awesome spectacle of scientific mapmaking, having for the first time accurately charted one of the world’s most topographically and climatically challenging regions. Finely lithographed hachures form the astoundingly extreme contours of the Himalayan peaks and valleys, while the heavily populated Valley of Kashmir, with the capital city of Srinagar and its famous lakes, occupies the upper centre, with further detail presented in the inset in lower left corner.
The survey of Jammu & Kashmir must be seen within the broader context of the Great Trigonometrical Survey (GTS) of India, a Herculean endeavor that lasted from 1802 to 1870. The objective of this mega-project was to construct baselines of triangulation chains, fixed by astronomical observations, running along the length and breadth of India. Once completed, these highly accurate baselines could be used as reliable commencement points for scientific and systematic regional surveys throughout India.
By 1855, the vast majority of the subcontinent had already been surveyed to the advanced standards of the GTS. That year Captain Thomas George Montgomerie, an especially promising young Scottish GTS member, was chosen to lead the Jammu & Kashmir survey. From 1856 to 1860, working under outrageously difficult conditions, even through the winters, Montgomerie and his team scaled mountains to points above 15,000 feet in altitude in order to erect base-points of triangulated readings. They also reassessed the heights of various Himalayan peaks as being over 30% higher than previously realized.
Montgomerie’s manuscript drafts were fashioned into an integrated map at the GTS field office in Dehra Dun and sent to London to be lithographed by the leading firm of J. & C Walker.