When the Seattle Transit Tunnel was developed in the late 1980s, the Metropolitan Transit Authority partnered with Jack Mackie, civic artist, to help bring the infrastructure project to life, quite literally. Five different varieties of trees—Oak, Ginko, Linden, Zelkova, and Maple—were planted on the city streets along the five transit stations where the tunnel runs underground.
The trees pay homage to Seattle’s lush landscape, but the true gems are the beautiful cast-iron tree grates installed on the ground around each trunk. At the foot of each of the trees is a custom-designed tree grate, each created by a different artist. That is paired with an informational plaque listing the tree species, artist name, and marking the location along the tunnel route.
The Tree Grate Museum is a cluster of all five trees, grates, and markers, planted together in one spot—a small grove at the Convention Place Station on 9th Avenue between Olive and Pine Street, on the east sidewalk. It functions as a sort of key that explains the expansive artwork that stretches through downtown.
The artists who created the Tree Grate designs are Dyan Rey, Virginia Paquette, Garth Edwards, Maren Hassinger, and Susan Point.
Update as of April 2021: The trees and grates have been temporarily removed to allow for the construction of the Washington State Convention Center extension. The building permit states that the plaques will be restored, but it’s unclear if new trees will be planted or the originals brought back.