Terrestrial cosmogenic nuclide surface exposure dating of moraine boulders and alluvial fan sediments defi ne the timing of fi ve glacial advances over at least the last fi ve glacial cycles in the Ladakh Range of the Transhimalaya. The glacial stages that have been identifi ed are: the Indus Valley glacial stage, dated at older than 430 ka; the Leh glacial stage occurring in the penultimate glacial cycle or older; the Kar glacial stage, occurring during the early part of the last glacial cycle; the Bazgo glacial stage, at its maximum during the middle of the last glacial cycle; and the early Holocene Khalling glacial stage. The exposure ages of the Indus Valley moraines are the oldest observed to date throughout the Himalayan orogen. We observe a pattern of progressively more restricted glaciation during the last fi ve glacial cycles, likely indicating a progressive reduction in the moisture supply necessary to sustain glaciation. A possible explanation is that uplift of Himalayan ranges to the south and/or of the Karakoram Mountains to the west of the region may have effectively blocked moisture supply by the south Asian summer monsoon and mid-latitude westerlies, respectively. Alternatively, this pattern of glaciation may refl ect a trend of progressively less extensive glaciation in mountain regions that has been observed globally throughout the Pleistocene.

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