Mountains to Sound Greenway Trust is a brand dedicated to preserving the natural landscapes and ecosystems of the Greenway National Heritage Area (NHA) in Washington state. Designated by Congress in March 2019, the Greenway NHA stretches 100 miles from Ellensburg to Seattle, encompassing a diverse corridor that includes water, mountains, forests, and farms. This ecologically rich region has deep cultural and historic significance, with a history of tribal presence and a network of travel and trade that stretches back millennia.

As the Coordinating Entity for the Greenway NHA, Mountains to Sound Greenway Trust works with local partners to achieve a range of goals, including amplifying the region's history and natural heritage through interpretive and educational programming, uplifting tribal heritage and involvement in stewardship, promoting pride of place and connections to nature, and protecting and stewarding natural, cultural, and historic resources. The Greenway Trust also engages in funding opportunities, promotes responsible recreation, and acts as a catalyst and convener for partnerships. Through its work, Mountains to Sound Greenway Trust ensures that the region's character and heritage are preserved, while also supporting tribal rights and recognizing the important role of tribal presence.

This designation as an NHA provides a tool to achieve these goals and engage the wider community in the stewardship of the Greenway NHA. By connecting people with nature and fostering appreciation for local heritage, Mountains to Sound Greenway Trust is working to create a more sustainable and inclusive future for the region