Curiosity nibbled at Steve Grate as he stopped on a Cougar Mountain trail near Issaquah. Why, he wondered, were there no condos or malls...

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Curiosity nibbled at Steve Grate as he stopped on a Cougar Mountain trail near Issaquah. Why, he wondered, were there no condos or malls where he stood when development was booming at lower elevations.

Research led him to the Issaquah Historical Society. He went back and forth between the books and history files and the trails on Cougar, Squak and Tiger mountains. He discovered the area was riddled with old coal mines. Outdoors, he searched for traces of long-gone houses, hotels and mining buildings; indoors, he sought maps and photographs.

Three years after he started, Grate has become an expert on Eastside mines, which once stretched from Renton to Bellevue and east to North Bend. He has pinpointed closed shafts and remnants of mining operations, consolidated multiple maps and located dozens of old photographs.

Grate uses that knowledge to guide Hikes into History for the historical society, tours designed to give participants a peek into what once was.

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For a century — 1863 to 1963 — the Eastside was a coal-mining center. One community, Newcastle, produced more than 200,000 tons of coal annually at its peak in the 1880s. It was the second-largest city in the county after Seattle, bustling with more than 600 homes, a rail line, hotels, stores and churches.

“There’s a ghost town … and most people haven’t seen it,” Grate said, referring to the historic site. “There are overgrown gardens by the house sites, rose bushes and raspberry bushes.”

He leads hikes to sealed mine entrances, air shafts and old building foundations, pointing out pieces of coal still lying around and piles of tailings.

Hikes into History Issaquah Historical Society offers two hikes in the coming weeks: Issaquah-Superior Mine hike, 10 a.m. Saturday, and the Grand Ridge Mine hike, 10 a.m. Nov. 12. The Issaquah-Superior hike takes about 2 ½ hours and covers two miles over easy terrain near downtown Issaquah. The Grand Ridge hike takes about four hours and covers between three and five miles, depending upon weather conditions. Both hikes begin with a free pre-hike presentation at Issaquah Depot, 50 Rainier Blvd. N. The hike fee is $5 per person, and reservations are required. You do not need to go on the hike to attend the pre-walk show. Call 425-392-3500 or e-mail

Other hiking guides: Several hiking trails in the Newcastle/south Bellevue area go through former coal-mining areas. Check hiking guidebooks such as “Hiking Trails of Cougar Mountain Wildland Park and Surrounds” available through the Issaquah Alps Trails Club or “Nature Walks In and Around Seattle” from The Mountaineers. The Issaquah Alps Trails Club also offers group hikes in the area. To learn more about the club, go to Mountains to Sound Greenway offers printed guides that include old mining areas. Go to

Other resources: Several books have been written on local coal-mining history, including “Black Diamond: Mining the Memories,” by the Black Diamond Historical Society; “Fire Rock — The Story of Issaquah’s Coal Mining History,” by Linda Adair Hjelm; and “The Coals of Newcastle” by Richard K. McDonald and Lucile McDonald.

The 54 recorded mines he has identified were all sealed by the federal government in 1986 and 1987. The few “gypo” or independent mines were shallow operations, and most of those tunnels have subsided or sunk.

“Old coal mines are sealed for a reason,” Grate said. “After 100 years of erosion and decay, they’re as unsafe as can be.”

Many mines went hundreds of feet underground, beneath the water table. Companies pumped water out during mining operations, but some tunnels are now flooded, said Grate. Because air tunnels also were sealed, methane gas permeates some mines. Timber supports have begun to deteriorate.

Early miners left pillars of coal in place to hold up chamber roofs, but in the 1950s companies cashed in, removing the solid coal supports and leaving the underground areas doubly dangerous.

Most of the mines are multi-story, like an underground apartment complex, to harvest some of the 12 different coal seams layered between dirt. Electric or steam-powered hoists and small rail cars carried crews down and coal up hundreds of feet. (Much coal remains underground. Geological reports indicate that only 40 percent of King County’s coal has been removed.)

Discovering where the old mines were has become a passion for Grate, who moved to Issaquah five years ago from Indiana. The 48-year-old independent computer consultant researched local geology and tracked down old mining maps and reports — a challenge since companies would frequently change hands and names.

“I hike the trails as exercise, but now I carry maps, a GPS and camera,” Grate said. “I talk to people along the way, and I’ve accumulated a lot of information. This isn’t lost history, but much of it is forgotten history.”

The Native Americans knew of coal and called it fire rock.

White settlers made their first discovery of coal outcroppings on Squak Mountain in 1859. The first commercial mine in Issaquah opened in 1862 and a year later in Renton. Eastside coal was shipped to San Francisco. Mine-company owners had no trouble attracting a high-quality labor force from back East and from Eastern Europe, the United Kingdom and Finland. That’s because local coal is a low-sulfur lignite and didn’t cause the dreaded black lung that crippled and killed miners elsewhere.

The last Eastside mine in Newcastle closed in 1963.

Much of the land above the mines is now parks or natural areas, owned by King County, Bellevue and Washington state. Grate has tremendous admiration for the preservation of the interconnecting parks that link Cougar, Squak and Tiger mountains — including King County’s Grand Ridge Park, which sits atop the former Grand Ridge Mine.

There’s a good reason, he learned, why there is so much open space — development hasn’t been allowed above many of the old mines because of the danger.

That hasn’t always been the case. Some of the development on the hill behind the Issaquah Fish Hatchery was built atop old mine shafts from the Jones Mine, the first mine in King County.

Last year, a sinkhole opened near Wildwood Boulevard.

“I predicted that,” Grate said. “There’s a lot of water flowing through those tunnels, and it erodes the ground. I was off by about 10 feet.”

Sherry Grindeland: 206-515-5633 or

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