The 58.60-mile (94.31 km) long roadway begins at U.S. Route 12 (US 12) in Morton and continues north to intersect several other state highways to Tacoma, where it ends at an interchange with Interstate 5 (I-5) and I-705.

In Elbe, the roadway intersects SR 706, which goes east to Mount Rainier National Park.

[10] Leaving Parkland and entering Tacoma, Pacific Avenue turns east as 38th Street and then has another partial cloverleaf interchange with a short freeway and the proposed route of SR 7, which is used by the roadway.

[17] Both highways were replaced by two branches of State Road 5 in 1923, which traveled from Tacoma to Mount Rainier and Elbe to Chehalis.

[2][22] The southernmost section of the highway between Kosmos and Morton was replaced in November 1967 with the relocation of US 12 as part of preparations for the Mossyrock Dam, which would create the Riffe Lake reservoir and inundate the area.

[31] On July 30, 2008, the Washington State Department of Transportation (WSDOT) had a groundbreaking ceremony to start construction of SR 704,[32] which was predicted to be finished after 2017.

[37][38][needs update] A small plane made an emergency landing on a section of SR 7 in Parkland on August 1, 2019, following a fuel system malfunction.