India, March 4 -- A nearly two-mile-long lake that once stretched across north Delhi has resurfaced; not on the ground, but on old maps.

While examining 19th and early 20th century maps for a recent exhibition of old charts and atlases, the Indian National Trust for Art and Cultural Heritage (Intach) identified traces of a massive water body north of Bhalswa Lake, much of which has been built over, though parts may still be revived, Intach officials said.

A comparison of a 1932 map of Delhi, which shows the water body spread across Qadipur and Nagli-Puna (present-day Kadipur), with current satellite imagery indicates that most of the area has now been built upon.

In a letter to the Delhi lieutenant governor (LG) and the Delhi Developme...