The intersection of Montlake and Lake Washington Boulevards was once a beautiful area. The tranquil Portage Bay sat to its west, the green wetlands of the Arboretum to the east, and the collegiate gothic buildings of University of Washington to the north just across a drawbridge.

Then the highway came.

In 1963, State Route 520 opened over the protests of the neighborhood and brought the roar of thousands of cars an hour. Victor Steinbrueck, an architect who helped design the Space Needle and saved Pike Place Market, called 520 "unimaginative" and full of "naked brutality." A 1956 letter to the editor in the Seattle Times called for choosing a different route for 520, so a highway wouldn't "mar the beauty of one of Seattle's outstanding assets."

Now, nearly 60 years after the highway opened, construction crews have broken ground on a $455 million project that will return some calm to the intersection. In addition to completely rebuilding SR 520 to make it more earthquake-safe, crews are covering the highway with a three-acre park that will help reunite the neighborhood the freeway divided.

Steve Peer, a spokesperson for the Washington State Department of Transportation (WSDOT), said this park, also known as a freeway lid, will be like taking the neighborhood back in a time machine.

"I think it will go back to a time in the 1950s when there wasn't a 520 bridge and it was more of a neighborhood," Peer said. "We can't go all the way back... but we certainly can reconnect the community better."

The Montlake Lid, expected to be done by 2024, will feature 1.5 acres of grassy parkland as well as space for a new bus stop that will have priority access to the six lanes of highway traffic running under the lid. Peer said it wasn't possible to know exactly how much the lid itself costs because it is structurally tied to other aspects of the project.

The lid will stretch between Montlake Boulevard East and 24th Avenue East. An earlier design extended the lid even farther east to the edge of Lake Washington and would have included more than twice as much park space, but that plan had to be reduced because of costs related to providing tunnel ventilation underneath the lid, according to Peer.

Montlake isn't the only spot on 520 getting a new lid. Farther west, WSDOT plans to build another lid over SR 520 between 10th Avenue East and Delmar Drive East. This second lid, which will be more than two acres, will feature a grassy park that better connects the Roanoke area with North Capitol Hill. WSDOT plans to finish construction of that lid by 2029 (but the project has been temporarily put on hold by Governor Jay Inslee while the state sorts out how to deal with transit funding after voters approved Initiative 976, which reduced car-tab fees while also cutting billions of dollars from the state's budget).

WSDOT's willingness to build these two lids, as well as new lids over 520 on the east side of the lake, show that the state is ready to take on more transformational projects like lids, according to Scott Bonjukian, one of the cochairs of the Lid I-5 group. His group is trying to convince the government to build an 18.5-acre lid over Interstate 5 in downtown Seattle.

"I think it shows both a willingness and an expertise to do lids," Bonjukian said. "That said, the I-5 corridor is a lot more complex—land-use wise, topographically, and in the amount of traffic. But generally, it shows that they're headed in the right direction."

The City of Seattle plans to release a new $1.2 million feasibility study in April about the I-5 lid. Peer said he couldn't comment on WSDOT building other lids in the future, but he said the agency is looking beyond just creating pavement for cars to drive on.

"The department of transportation isn't just about highways anymore," Peer said. "Maybe in the 1960s it was more about moving cars—now it's about moving people."