DeLong Mountains, exploration. In August Craig Deutche, Anne Machung, Jerry Weidler, and I established a new route across the DeLong Mountains from Howard Pass to Desperation Lake. We were studying the landscapes and ecology of Petroleum Reserve no4. From Kavaksurak we ascended the Ipnavik River to its source in the unexplored nexus of peaks and passes that eventually subside into the Makpik Drainage above Feniak Lake. We passed through the Holocene lake basins on the north side of the vast, complex Siniktaneyak Massif and made the first ascent of its summit above the central cirque. This expedition was part of a larger historical effort to comprehensively explore the entire Brooks Range.