Sedro-Woolley is a city in Skagit County, Washington, United States. It is allowance of the Mount Vernon–Anacortes, Washington Metropolitan Statistical Area and had a population of 10,540 at the 2010 census. The city is home to North Cascades National Park.

Officially incorporated upon December 19, 1898, Sedro-Woolley was formed from against rival towns known as Bug and Woolley in Skagit County, northwestern Washington, 25 miles (40 km) inland from the Puget Sound, 40 miles (64 km) south of the affix with Canada and 65 miles (105 km) north of Seattle.

Four British bachelors, led by David Batey, homesteaded the area in 1878, the period logjam obstructions were cleared downriver at the site of Mount Vernon. In 1884–85, Batey built a buildup and house for the beginning of the Mortimer Cook relatives from Santa Barbara, California where Cook had been mayor for two terms. Cook intended to say his further Pacific Northwest town Bug due to the number of mosquitos present, but his wife protested along afterward a handful of further local wives. Cook was already the namesake for the town Cook’s Ferry upon the Thompson River in British Columbia. With “Bug” being for that reason unpopular, Cook derived a town post from Spanish; knowing “cedro” was the word for cedar, he replaced one letter to make the post unique, settling on “Sedro”.

Sedro, on the northern banks of the Skagit River, proved susceptible to floods. In 1889, Northern Pacific Railway developer Nelson Bennett began laying track from the town of Fairhaven, 25 miles (40 km) northwest on Bellingham Bay, and genuine estate developer Norman R. Kelley platted a extra town of Sedro on high ground a mile northwest of Cook’s site. The Fairhaven and Southern Railroad arrived in Sedro upon Christmas Eve 1889, in period for Bennett to receive a behave bonus from the towns at both ends, and a month after Washington became the 42nd let pass in the Union.

Within months, two more railroads crossed the F&S road bed a half mile north of further Sedro, forming a triangle where 11 trains eventually arrived daily. Railroad developer Philip A. Woolley moved his intimates from Elgin, Illinois, to Sedro in December 1899 and bought land approaching the triangle. He built the Skagit River Lumber & Shingle Mill neighboring where the railroads crossed and he started his namesake company town there that was based on sales of railroad ties to the three rail companies, including the Seattle and Northern Railway (forerunner of the Great Northern Railway) and the Northern Pacific Railroad.