After Sati dies in her father's fire, Shiva carries her body across the world weeping, and two tears become the lakes of Pushkar and Katas. Katas in the Salt Range of Punjab drew pilgrims to bathe at Baisakhi for centuries, and is also told as the lake of the Yaksha's questions.
Shiva and Sati spent their married years in the Salt Range. When Sati gave up her life at Daksha's sacrifice, Shiva wandered the world with her body, weeping, and two of his tears fell and became pools, one at Pushkar in Rajasthan and one at Katas, whose name comes from kataksha, tearful eyes. The earth's two eyes, Pushkar the right and Katas the left, drew pilgrims; at Katas they bathed on Baisakhi, and the pool is also held to be the lake where the Yaksha questioned the Pandavas.
Sources: Katas Raj temples (Punjab Tourism, Pakistan; Wikipedia; Daily Times); The forgotten gurdwara: Guru Nanak at Katas Raj (SikhNet), citing Sujan Rai Bhandari (1695), Giani Gian Singh (1880) and James Abbott (1848)