Peterson Lagoon is the estuary of Peterson Creek, which flows north-northwest for four miles (7 km) from the outlet of Peterson Lake, at 734 feet (224 m) on Auke Mountain, to a tidal lagoon that connects to Eagle Harbor, about 56 miles (90 km) south-southeast of Haines and 19 miles (31 km) northwest of Juneau, Alaska. Eagle Harbor is a cove about half a mile (0.8 km) across on the eastern shore of Favorite Channel. The area lies on the western edge of the Coast Mountains, where gold-bearing quartz veins that formed 56-55 million years ago cut metamorphosed sedimentary and volcanic rock. These veins form the Juneau Gold Belt, more than 200 deposits in a zone 99 miles (160 km) long and three to five miles (5-8 km) wide that have yielded nearly 7 million ounces (about 218 tonnes) of gold. Peterson Lake and Creek were named for John G. Peterson, a German-born Juneau businessman and miner who arrived in 1888 and initially worked as a tinsmith. In the late 1890s he staked claims and later operated a hard-rock mine half a mile (0.8 km) east of the lake, crushing ore with a three-stamp mill. Workings included four shafts, 11 adits and numerous trenches. His wife, Marie, and their daughters ran the mine after his death in 1916.

Peterson Creek is a spawning stream for Pacific salmon, steelhead and Dolly Varden. The temperate rainforest of Southeast Alaska has thousands of salmon streams, which historically provided the economic foundation of the Tlingit people. Their culture rested on capturing, processing and storing salmon in quantities that left surpluses to eat and barter through the winter. Techniques varied by locale. The Chilkoot gaffed or speared salmon from boulders and small wooden platforms. The Yakutat Tlingit built weirs and traps along streams. The Auk Tlingit, whose territory includes Juneau, used wooden stake weirs and intertidal stone walls to funnel fish into woven cylindrical baskets. A basket trap 500-700 years old was excavated from nearby Montana Creek in 1991. Because such methods let many fish escape to the spawning beds, they sustained the runs. Today Peterson Creek is a popular sport-fishing stream because a road from Juneau passes nearby. But coho returning to the creek failed to meet the sustainable escapement goal set by the Alaska Department of Fish and Game in four of the past seven years, according to a 2026 emergency order, and the creek is closed to coho fishing through December 31. It has also been closed to all sport fishing each spring to protect a declining steelhead run.

Peterson Lagoon lies beside Ernest Gruening State Historical Park, a 12-acre site managed by Alaska State Parks. Ernest H. Gruening was a journalist and politician who governed the Alaska Territory from 1939 to 1953 and represented Alaska in the United States Senate from 1959 to 1969. His cabin, built in 1947 and listed on the National Register of Historic Places in 1992, stands beside the lagoon. The park says he wrote much of his statehood manifesto there, titled The State of Alaska and published in 1954. The cabin, called “Eagle Rock”, hosted national and foreign leaders, including Adlai Stevenson, Earl Warren, then governor of California, and numerous senators. Since 2015 the cabin has hosted an artist-in-residence program, open from May to September for stays of up to two weeks, which honors Dorothy Gruening, an avid painter and Gruening’s wife, and Rie Muñoz. Muñoz was known for bright watercolors of everyday life in Alaska, particularly in Alaska Native villages and Southeast Alaska. Read more here and here. Explore more of Peterson Lagoon and Eagle Harbor here: