Few cities allow you to peek below the surface and see the history they’re built upon quite like Seattle.

After the Great Fire of 1889 burned 25 downtown blocks and displaced thousands, officials were forced to make some changes. Wooden buildings were banned in the central business district, the City took control of the privately owned water supply (sparsely located hydrants and small pipes had doomed the firefighting effort), and the streets were raised by as much as 22 feet in some places, helping to even the hilly city and prevent flooding.

To make the underground passageways created by the regrading usable and lit, business owners installed prism glass in the new sidewalks. And out of necessity, a beautiful part of Seattle’s urban fabric was born.

Nowhere in the city can you find more prism glass than the historic Pioneer Square neighborhood, a diverse and bustling area in the southwest corner of downtown. But after a century of foot traffic, many of the colorful implants have worn down or been discarded altogether. And replacing them, which can trigger a slew of engineering, is expensive.

“Something as simple as repairing a glass walk can get really complicated really fast,” says Carl Leighty, Public Realm Coordinator for the Alliance for Pioneer Square, a nonprofit community group. “That’s why they’re not in the greatest shape.”

Partnering with the Alliance, the National Trust has launched a crowdfunding campaign to fully restore the glass in front of the iconic Smith Tower as part of The Cities Project by Heineken. The project will serve as an example of how the glass can be replaced and maintained so that generations to come can enjoy this unique vestige of Seattle’s history.

The work will also help to keep the neighborhood’s public spaces beautiful. Pioneer Square has long been one of Seattle’s most distinct and diverse areas, attracting an eclectic mix of people against a backdrop of turn-of-the-century architectural consistency; most of the neighborhood was rebuilt in the same style following the fire. It’s both where much of Seattle’s creative class comes to work and where the City confronts some of its toughest challenges.

“[Pioneer Square] has been cared for yet neglected,” says Leighty, “so there’s definitely a sense of community. It’s a very dynamic neighborhood because we do have probably the highest concentration of social services and human services, and there are a lot of people down here to receive those services and then during the day we have this influx of high-end tech workers. There’s a diversity of people that we think is an asset and we try to celebrate that. That’s why we work to improve our public spaces and make them accessible to everyone.”