Are these eleven hundred islands actually just the peaks of submerged coastal mountains?

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Spanning three hundred miles off the Alaskan coast, the Alexander Archipelago is a rugged labyrinth of over one thousand islands. These landmasses are the summits of ancient mountains drowned by the Pacific, creating a dense, rain-forested maze that remains largely accessible only by boat or by small aircraft.

The archipelago serves as a natural barrier for the Inside Passage, with deep fjords and channels carving through the landscape. Geologically, these islands are the exposed tops of a massive, submerged coastal mountain range. The terrain is defined by steep, irregular coastlines and thick temperate rainforests, most of which fall under the protection of the Tongass National Forest. Wildlife is abundant across the chain, which includes major landmasses like Prince of Wales, Chichagof, and Admiralty Islands.

Human history in the region is deep and layered. The Tlingit and Kaigani Haida are the indigenous inhabitants of this territory. In contrast, the Tsimshian population on Annette Island arrived later, migrating from British Columbia during the late 1800s. European exploration began in 1741 with the Russian navigator Aleksei Chirikov, followed by Spanish explorers like Juan José Pérez Hernández and Jacinto Caamaño. By the 1790s, George Vancouver conducted extensive surveys, mapping the complex straits and passages that define the archipelago's geography.

The naming of the islands reflects the region's shifting geopolitical history. Before the 1867 Alaska Purchase transferred control from Russia to the United States, the chain appeared on an 1860 map as the King George III Archipelago. Following the purchase, the U.S. Coast and Geodetic Survey renamed the group in honor of Tsar Alexander II of Russia. Today, the islands remain a vital hub for fishing, logging, and tourism, with major settlements like Sitka and Ketchikan serving as the primary gateways to this remote, mountainous wilderness.

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