More than a century ago, James Phinney Baxter envisioned an impressive park system for Portland, and after becoming mayor in 1893 following a successful business career, he worked with the firm Olmsted, Olmsted and Eliot to promote a "City Beautiful" of connected parks, waterways, and roadways that would strengthen both the city's economy and its natural beauty. After many political battles over the next quarter century, that vision took shape with the opening of Back Cove Boulevard in 1920, later renamed Baxter Boulevard. On Arbor Day in 1920, the original fifty Linden trees along the boulevard were planted, each bearing a brass plate with the name of someone who died in World War I, and the American Legion later helped add more trees to this legacy. Several original features, including the granite ellipse with benches and sundial on the west side of the Vannah Avenue intersection and the cobble gutters, still remain. In 1989, Baxter Boulevard was listed in the National Register of Historic Places, and today this significant designed landscape is protected under Portland's historic preservation ordinance along with Deering Oaks, Lincoln Park, and the Eastern and Western Promenade. The trail is now three and a half miles long, marked in quarter-mile increments with kilometer equivalents, with one five-kilometer sign in the clockwise direction. Baxter's broader vision of an interconnected "emerald necklace" of parks including Back Cove, the Eastern and Western Promenades, Evergreen Cemetery, and Deering Oaks was greatly expanded in the 1980s by the city's Shoreway Access Plan, which proposed trails linking Portland's parks, marshes, rivers, and coastline. Since its founding in 1991, Portland Trails, a nonprofit land trust, has helped carry out these plans by preserving green space for public access, connecting people with places, working to create and maintain a fifty-mile trail network in greater Portland, encouraging participation by neighborhoods, schools, and businesses in trail use and land stewardship, and promoting greater Portland as a model for people-powered recreation and transportation.