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San Juan Islands

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The San Juan Islands are a beautiful archipelago located in the Pacific Northwest of the United States.

They sit in the waters between Washington state and Vancouver Island in British Columbia, Canada. The United States Geological Survey defines this group as the islands north of the Strait of Juan de Fuca. They are also west of the Rosario Strait and east of the Haro Strait. These islands form the core of San Juan County in Washington.

San Juan Islands aerial
San Juan Islands aerial

While they are politically part of the U.S., they are geologically part of a larger Gulf Archipelago. This group includes the Canadian Gulf Islands as well.

The geography of the archipelago is quite diverse and complex. At mean high tide, the San Juan Islands include over 400 islands and rocks. Out of these, 128 are specifically named. The landscape is mostly hilly, though there are some flat, fertile valleys. The highest point in the islands is Mount Constitution. It is located on Orcas Island and reaches a high elevation.

View from ISS Expedition 72, San Juan Islands, October 7, 2024 (ISS072-E-34209)
View from ISS Expedition 72, San Juan Islands, October 7, 2024 (ISS072-E-34209)

The coastlines vary between sandy beaches and rocky shores. You can find shallow inlets, deep harbors, and quiet coves throughout the area.

Nature is very active in this region. The islands are home to the largest concentration of bald eagles in the contiguous United States. Many different types of trees grow in the forests. You can see second-growth forests with Douglas fir, Pacific madrone, and red alder. There are also small areas of old-growth western redcedar.

Iceberg Point Lopez Island Washington USA
Iceberg Point Lopez Island Washington USA

In the higher lands, you might find grand fir and western hemlock. The islands also host many birds, such as peregrine falcons and barred owls. In the water, many different species of birds and marine mammals live.

The waters around the islands are part of the Salish Sea. This name includes the Puget Sound and the Straits of Georgia and Juan de Fuca. The sea is famous for its resident pods of orcas. There are three resident pods that eat salmon. There are also transient orcas that hunt harbor seals.

SanJuanIslandAtNight
SanJuanIslandAtNight

Other marine life includes Steller sea lions, minke whales, and Dall's porpoises. The islands also host Columbia black-tailed deer. These are the largest mammals found on the islands. Historically, wolves lived here, but they were removed in the 1860s.

History in the islands began with the Coast Salish peoples. This includes groups like the Nooksack and the Northern Straits. Later, European explorers arrived in the area. In 1790, Manuel Quimper encountered the islands during an exploring voyage. In 1791, Francisco de Eliza named the islands Isla y Archipiélago de San Juan. He named several places after the Viceroy of Mexico. For example, Orcas Island was named after Horcasitas.

American Camp, San Juan Island, July 4, 1867
American Camp, San Juan Island, July 4, 1867

In 1792, George Vancouver and a Spanish expedition explored the area together. They even traded information to help their mapping efforts.

A major border dispute once divided the region. The 1846 Oregon Treaty set a border at the 49th parallel. However, the treaty did not say which water channel would be the border. This caused a conflict between the United States and Britain. This event is known as the Pig War or the San Juan Dispute. It was a diplomatic stalemate for many years. In 1871, the issue was sent to Emperor Wilhelm I of Germany for arbitration. He decided the border should run through the Haro Strait. This was finalized in 1872.

Today, the islands are a significant place for both nature and travel. Four of the islands are accessible to people by car or on foot. This is possible through the Washington State Ferry system. Some areas are protected within the San Juan Islands National Monument. This monument includes 75 sections of land. The islands remain a place where history, biology, and geography all meet in the sea.

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🖼️ Images & Media (6)
File:San Juan Islands map.png
San Juan Islands map.png
File:View from ISS Expedition 72, San Juan Islands, October 7, 2024 (ISS072-E-34209).jpg
View from ISS Expedition 72, San Juan...
File:Iceberg Point Lopez Island Washington USA.jpeg
Iceberg Point Lopez Island Washington USA.jpeg
File:American Camp, San Juan Island, July 4, 1867.jpg
American Camp, San Juan Island, July 4, 1867.jpg
File:SanJuanIslandAtNight.JPG
SanJuanIslandAtNight.JPG
File:San Juan Islands aerial.jpg
San Juan Islands aerial.jpg
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