Humayun's Garden Tomb is essentially a mausoleum that sits in a large garden with a char bagh plan.
A char bagh garden is a garden that is divided by two intersecting channels of water.1 Catherine Asher explains why Humayun's Garden Tomb is considered a char bagh garden and what this means.
Upon entering any gate, the centrally situated tomb and its char bagh setting are visible. Each of the four garden plots is further sub-divided by narrower waterways. Based on the char bagh types established in Iran and more fully developed in Babur's own concept of the ideal garden, such formalized and geometrically planned garden settings became standard for all the imperial Mughal mausoleum and for those of many nobles as well. Char bagh gardens long had been associated with paradisiacal imagery. But at Humayun's tomb, the association is all the more explicit, for the water channels appear to vanish beneath the actual mausoleum yet reappear in their same straight course on the opposite side. This evokes a Qu'ranic verse which describes rivers flowing beneath gardens of paradise.2
1. Catherine B. Asher, The Architecture of Mughal India (Cambridge: Cambridge University Press, 1992), xxv.
2. ibid., 45.
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