The pool now known as the Amrit Sarovar traces to a plot of land Guru Amar Das, the third Sikh Guru, identified for a new settlement, which his successor Guru Ram Das began developing in the 1570s. Under Guru Ram Das the excavation of a sacred tank began in earnest, and the settlement that grew up around it took the name Ramdaspur before later becoming Amritsar, a name built directly from Amrit Sarovar, the Pool of Nectar. The fifth Guru, Arjan, completed the tank's construction and, in 1604, built the Harmandir Sahib at its center and installed the newly compiled Adi Granth, the precursor to the Guru Granth Sahib, within it, uniting the site's water, temple and scripture into the complex that remains Sikhism's most important place of pilgrimage.
Guru Arjan designed the Harmandir Sahib with doors on all four sides, open to people of any caste or background, an architectural statement of the egalitarian teaching central to Sikhism, and set the temple lower than the surrounding ground, reachable by a descending causeway across the water, so that a worshipper must walk down toward it rather than up, a deliberate rejection of the raised, hierarchical siting common to many temple traditions of the surrounding region.