2021 Map of Umnak B-1 SW

About this map

Hourglass Pass and Bottleneck Pass define the high-altitude crossings of this volcanic island landscape in the Aleutians West. The terrain is marked by steep elevation changes, with the land eventually descending south toward the vast shoreline of the Pacific Ocean. This 2021 survey illustrates the topographical complexity of Umnak Island, where the narrow corridors of these passes serve as the primary natural landmarks across the interior. While the map is devoid of human settlements or infrastructure, the naming of these specific mountain gaps suggests their importance for navigation through the island's interior ranges.