Rockdale is an extinct town in the

northwest The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A '' compass rose'' is primarily composed of four cardinal directions—north, east, south, and west— ...

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, in King County,

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

. The

GNIS The Geographic Names Information System (GNIS) is a database of name and location information about more than two million physical and cultural features, encompassing the United States and its territories; the associated states of the Marshal ...

classifies it as a populated place. A post office called "Rockdale" was established in 1912, and remained in operation until 1915. The community in the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington (state), Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as m ...

was named for the abundance of rock near the original town site. Just south of Snoqualmie Pass, it was at the west portal of the

Snoqualmie Tunnel The Snoqualmie Tunnel is a former Rail Transport, railroad tunnel near Snoqualmie Pass in the U.S. state of Washington (state), Washington, located east of Seattle. The tunnel crosses the Cascade Range about south of the pass, which is used by ...

, constructed by the Chicago, Milwaukee, St. Paul and Pacific Railroad (The Milwaukee Road) from 1912 to 1914. The

elevation The elevation of a geographic location (geography), ''location'' is its height above or below a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational equipotenti ...

is approximately above

sea level Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical ...

; it is south of and about above the eastbound lanes of

Interstate 90 Interstate 90 (I-90) is an east–west transcontinental freeway and the longest Interstate Highway in the United States at . It begins in Seattle, Washington, and travels through the Pacific Northwest, Mountain states, Mountain West, Great Pla ...

, formerly

U.S. Route 10 U.S. Route 10 or U.S. Highway 10 (US 10) is an east–west United States Numbered Highway located in the Midwest and Great Lakes regions of the U.S. Despite the "0" as the last digit in the number, US 10 is no longer a cross- ...

. The tunnel and right-of-way is now a

rail trail A rail trail or railway walk is a shared-use path on a Right of way#Rail right of way, railway right of way. Rail trails are typically constructed after a railway has been abandoned and the track has been removed but may also share the rail corr ...

, part of

Iron Horse State Park The Palouse to Cascades State Park Trail, formerly known as the John Wayne Pioneer Trail and the Iron Horse Trail, is a rail trail that spans most of the U.S. state of Washington (state), Washington. It follows the former railway roadbed of the ...

References

Ghost towns in King County, Washington Ghost towns in Washington (state) Geography of King County, Washington {{Ghost-town-stub