Allegany is an unincorporated community in Coos County

Coos County, Oregon

-National protected areas:*Bandon Marsh National Wildlife Refuge*Oregon Islands National Wildlife Refuge *Siskiyou National Forest *Siuslaw National Forest - Incorporated cities:- Unincorporated communities and CDPs:-See also:...

, Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

, United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 east of Coos Bay

Coos Bay, Oregon

Coos Bay is a city located in Coos County, Oregon, United States, where the Coos River enters Coos Bay on the Pacific Ocean. The city borders the city of North Bend, and together they are often referred to as one entity called either Coos Bay-North Bend or the Bay Area...

. According to Oregon Geographic Names

Oregon Geographic Names

Oregon Geographic Names is an authoritative compilation of the origin and meaning of place names in the U.S. state of Oregon. , the book is in its seventh edition and is compiled and edited by Lewis L. McArthur, who took over from his father, Lewis A. McArthur, as of the fourth edition...

, a post office was established there in 1893, and it is unknown why this spelling was chosen rather than the more common form, Allegheny

Allegheny

- Geologic and geographic features :* Allegheny River, in Pennsylvania and New York* Allegheny Mountains, part of the Appalachian Mountain Range in West Virginia, Pennsylvania, Maryland and Virginia...

, used for many features in the eastern United States.

The East Fork Millicoma River

East Fork Millicoma River

The East Fork Millicoma River is a tributary, about long, of the Millicoma River in the U.S. state of Oregon. Rising in eastern Coos County, it flows generally west to the community of Allegany, where it joins the West Fork Millicoma River to form the Millicoma. In turn, the Millicoma, which is...

 and West Fork Millicoma River

West Fork Millicoma River

The West Fork Millicoma River is a tributary, about long, of the Millicoma River in the U.S. state of Oregon. Rising in northeastern Coos County near the Douglas County line, it flows generally southwest through the Elliott State Forest of the Southern Oregon Coast Range to the community of...

 join at Allegany to form the Millicoma River

Millicoma River

The Millicoma River is a coast stream, about long, east of Coos Bay in the U.S. state of Oregon. Formed by the confluence of the East Fork Millicoma River and the West Fork Millicoma River at Allegany, it meanders across relatively flat land to meet the South Fork Coos River, with which it forms...

, a short tributary of the Coos River

Coos River

The Coos River flows for about into Coos Bay along the Pacific coast of southwest Oregon in the United States. Formed by the confluence of its major tributaries, the South Fork Coos River and the Millicoma River, it drains an important timber-producing region of the Southern Oregon Coast Range...

. The Golden and Silver Falls State Natural Area

Golden and Silver Falls State Natural Area

Golden and Silver Falls State Natural Area is a state park in Coos County, Oregon United States, administered by the Oregon Parks and Recreation Department. The nearest settlement is Allegany....

is a state park northeast of Allegany.