A northwest Washington point of pride in Whatcom County and Skagit County is noting that area on the border of the two counties is where the Cascade Mountains touch the sea.
Where the mountains touch the sea
Chuckanut and Blanchard Mountains on the right horizon
Lummi Peak just right of center
Mount Constitution just left of center
A range of low mountains extends west of the North Cascades in the area and reaches the Salish Sea. The range extends out into the San Juan Islands. The ridges and summits are relatively modest with summits near the water just under 3,000 feet with higher ridges inland and lower summits in the islands. Never the less the range forms a belt of rugged landscape that cuts across the otherwise continuous north-south Willamette-Puget lowlands that extend the entire length of the west side of the state.
Interstate 5 weaves through the range through a narrow low gap between Skagit County and Whatcom County. Another road, State Highway 11, or Chuckanut Drive, follows the coast at the base of Chuckanut Mountain along the shore of Samish Bay and Bellingham Bay. It ranks as one of the most scenic drives in the State and is a route I have never tired of. It also has lots of unstable slopes and rockfall hazards.
There is no formal name for the range and it really is a combination of uplifts and tectonics that overlap in a manner that does not brink out a distinct name. Locally the westernmost range that descends to the water at Chuckanut Drive and is passed across by I-5 is often called The Chuckanuts.
On a broader scale that incorporates the wider western extension of summits utilizes the term Northwest Cascades. I utilize that term more frequently as it gets at the distinct geology although extremely complex geology and can very reasonably be extended to cover the rugged peaks in the San Juan Islands. This more geologic term is extended to the east to the Straight Creek Fault, a major strike-slip fault with markedly different geologic units on the other side to the east where the core of the North Cascade Range begins.