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The timing of crustal melting and cooling has been investigated across the migmatites of the Greater Himalayan Crystalline Complex (GHC) in the Nyalam region, central Himalaya. Monazite U-Pb ages vary from 32 to 14 Ma and are linked to metamorphic conditions on the basis of monazite internal zoning, mineral inclusions, and changes in heavy rare earth element and Y composition. Metamorphic temperatures were estimated by Zr-in-rutile thermometry and cooling rates were further constrained by rutile U-Pb ages. The results reveal two distinct blocks within the GHC of the Nyalam region. The upper GHC experienced higher peak metamorphic temperatures (730-750°C) and a higher degree of melting (15-25%). Partial melting was dominated by muscovite dehydration melting, which lasted from ~32 to 25 Ma, possibly until ~20 Ma. The lower GHC experienced lower peak metamorphic temperatures (640-675°C) and a lower degree of melting (0-10%) mainly via H2O-saturated melting from 19 to 16 Ma. At different times, both upper and lower blocks experienced initial slow cooling (rates 35 ± 8 and 10 ± 5°C Ma-1, respectively) followed by rapid cooling (100 ± 20°C Ma-1). The documented diachronous metamorphism implies the presence of the 'High Himalayan Thrust' that was active at ~25-16 Ma within the GHC of the central Himalaya. Different degrees and durations of partial melting in the investigated section suggest that a channel flow process dominated the exhumation of the upper GHC migmatites at 25-16Ma, whereas a critical taper process dominated the exhumation of the relatively lower-grade lower GHC rocks and cooled upper GHC migmatites at 16-10 Ma. We suggest that propagating thrusts along large tectonic boundaries together with low-viscosity lateral crustal flow could contribute to exhumation of high-grade metamorphic rocks in the Himalaya and other similar collisional orogens. [ABSTRACT FROM AUTHOR]