Welcome to the Mountains to Sound Greenway National Heritage Area

The Mountains to Sound Greenway National Heritage Area is a unique geographic corridor made up of connected ecosystems and communities spanning 1.5 million acres from Seattle to Ellensburg along Interstate-90 in Washington state.

The Mountains to Sound Greenway Trust has been working for 35 years to conserve and enhance this incredible landscape — building and maintaining trails, restoring wildlife habitat, and connecting youth to the outdoors through environmental education. Through our mission, we strive for a long-term balance between people and nature.