Washington State is a major transportation hub in the Pacific Northwest, with several major freeways running through the state, helping to connect regions. Here are the major freeways in Washington State and their features:

I-5 (Interstate 5)

• Length: Approximately 276 miles (444 km) within Washington State.
• Role: A major highway running north-south along the U.S. West Coast, connecting Washington State from the south (Oregon) to the north (Canada).
• Major Cities:
  • Vancouver
  • Olympia (capital)
  • Tacoma
  • Seattle
  • Everett
  • Bellingham
• Features:
  • Passes through Seattle, the economic center of the state, with heavy traffic and congestion.
  • Connects to British Columbia, Canada at the northern end.

I-90 (Interstate 90)

• Length: Approximately 297 miles (478 km) within Washington State.
• Role: The longest highway connecting the east-west axis of the U.S., starting from Seattle at the western end and extending eastward.
• Major Cities:
  • Seattle
  • Snoqualmie
  • Ellensburg
  • Moses Lake
  • Spokane
• Features:
  • Connects Seattle to Spokane and on to Idaho.
  • A scenic highway that passes through Snoqualmie Pass.

I-405 (Interstate 405)

• Length: Approximately 30 miles (48 km).
• Role: Circles the eastern suburbs of Seattle and connects to I-5.
• Major Cities:
  • Bellevue
  • Kirkland
  • Renton
  • Bothell
• Features:
  • An alternative route to reduce traffic congestion in Seattle.
  • Passes through areas with major tech companies and suburban regions.

US Route 2

• Length: Approximately 326 miles (525 km) within Washington State.
• Role: A major road running east-west across northern Washington State.
• Major Cities:
  • Everett
  • Leavenworth
  • Spokane
• Features:
  • Famous for its scenic byway, passing through Stevens Pass.
  • An important route connecting eastern and western Washington.

WA-520 (State Route 520)

• Length: Approximately 12 miles (19 km).
• Role: Connects Seattle to the Eastside region (Bellevue, Redmond).
• Features:
  • The 520 Bridge crossing Lake Washington is one of the longest floating bridges in the world.
  • Connects to Redmond, home to Microsoft headquarters.

I-82 (Interstate 82)

• Length: Approximately 144 miles (232 km).
• Role: A major highway in eastern Washington, starting from Yakima and connecting to Oregon.
• Major Cities:
  • Yakima
  • Richland
  • Kennewick
• Features:
  • Connects to the agricultural hub of Yakima Valley.
  • Passes through the economic hub of the Tri-Cities (Richland, Kennewick, Pasco).

I-705 (Interstate 705)

• Length: Approximately 1.5 miles (2.4 km).
• Role: A short highway connecting downtown Tacoma to I-5.
• Features:
  • An important road connecting downtown Tacoma and the port area.

These freeways connect the cities and regions of Washington State, playing a key role in the movement of residents and businesses.

In particular, I-5 and I-90 function as the backbone of the state's transportation network, making significant contributions to the state's economy and logistics.