A 1.5-million acre swath of land surrounding Interstate 90, from Seattle to Ellensburg, is now a National Heritage Area, after the passage of the largest public-lands bill in more than a decade.

The wide-ranging, bipartisan bill that President Donald Trump signed into law Tuesday authorizes the Mountains to Sound Greenway as a National Heritage Area, one of dozens of measures in the more than 660-page bill intended to bolster public lands and conservation across the country.

The new heritage area spans 2,400 miles and includes 28 cities and 1,600 miles of trails, according to U.S. Sen. Maria Cantwell, a lead sponsor of the legislation.

A National Heritage designation does not make the land a part of the National Parks system, and private land within the area is not affected. Rather, the designation makes it easier for the area to get technical assistance and federal grants from the National Park Service.

National Heritage areas generally get somewhere between $150,000 and $750,000 annually, according to the National Park Service. The designation also helps with marketing and tourism promotion.

Members of Washington’s congressional delegation first introduced legislation to create the National Heritage Area in 2013.

“Washington state’s recreation economy generates $26 billion in annual spending and supports more than 200,000 direct jobs,” said Cantwell, a Democrat from Washington state. “Continuing to protect our most scenic and historic landscapes, like the Mountains to Sound Greenway, will help boost tourism and preserve our natural landscape for future generations.”