Some 100,000 car-racing fans are expected to mob Sonoma Raceway next Sunday, June 23, for one of the biggest National Association for Stock Car Auto Racing (NASCAR) events of the year.

But about 40 of those attending aren't really going there for the Toyota/Save Mart 350, the latest stop in the NASCAR Sprint Cup Series. In fact, they don't care about race cars at all.

They just came for the train ride.

Part of a loose nationwide network of railroad enthusiasts who call themselves "Rare Milers," these restless travelers will go anywhere, as long as they can travel by train.

For them, the first-ever NASCAR Express, departing at 8 a.m. next Sunday from Sacramento and running to the Sonoma Raceway and back, with a long stopover for the car race, is too good to resist.

"If you take the section of railroad track from American Canyon to the raceway, as far as we can determine, there never has been passenger rail service on these tracks," said Steve Page, general manger of Sonoma Raceway.

"The Carneros vineyard region is one of the most spectacular, beautiful areas in the world, and the train is going right through there," he said.

Passenger train service itself has become a rarity in Sonoma County, where regular service ended in 1958.

This train has room for 500 passengers and was nearly sold out earlier this week, so the train fanatics, sometimes described as "mileage collectors," are a small minority of the riders.

But for them, the journey itself is more appealing than the destination.

"I've never been to a car race, but I guess I'm going to one now," said Bob Douglas, 70, of Wyckoff, N.J., a retired nuclear and environmental engineer, one of the Rare Milers with reservations, each priced at $199, on the NASCAR Express.

Rare Milers track their travels in different ways, with many marking red lines on railway maps and others adding up the mileage. Douglas only counts the "new miles" of track he hasn't traveled before, and still racked up 4,000 miles last year.

The Wall Street Journal estimated last year there are 300 Rare Milers in the United States. It's a loose-knit, informal group with no meetings, dues or charter, communicating mainly via the Internet.

Rare Milers tend to know each other. Brad Phillips, 66, chief financial officer of Simco Electronics in Sunnyvale, first met Bill Crawford of the Boston area in the mid-1990s, on a train trip at McCloud, near Mount Shasta. Both men will ride the NASCAR Express.

"This is a category of folks that just like to ride trains," Phillips said. "It's the journey, and the destination, but for a lot of us, it's really about marking another line on the map."

Mileage collectors will resort to plane or car travel to reach the desired stretch of railroad track, but ultimately, it's all about the trains.

"The goal is to ride the train in places where you can't ride ordinarily. A lot of track has been used only for freight," said Crawford, 69, a recently retired industrial metallurgist from Nahant, Mass., a Boston suburb.

"A trip like this one to American Canyon will bring out many of the people in this hobby," Crawford added. "This is some very rare mileage."

The NASCAR Express will travel on the Union Pacific mainline from Sacramento via Davis and Suisun-Fairfield to Suisun Junction, then over Union Pacific-owned tracks operated by the California Northern Railroad from Suisun Junction and Napa Junction to Brazos Junction.

It will continue over SMART-owned tracks operated by Northwestern Pacific from Brazos Junction to the Sonoma Raceway at Sears Point, just north of the State Highway 37 grade crossing.

"There are lots of agencies involved. It has probably taken the better part of a year just to put all the specifics together," said Page, of Sonoma Raceway.

"This is my 22nd NASCAR event since I came to the track," he added, "and I've been trying to bring fans in on the railroad ever since I got here. So this is the culmination of about 22 years of effort."

Brisk ticket sales for the NASCAR Express have made Page optimistic about booking more excursion trains to Sonoma Raceway in the future.

"You're not dealing with traffic or parking," Page said, "and on the way home you have a designated driver with a striped hat and a train whistle."

For more information: www.racesonoma.com

(You can reach Staff Writer Dan Taylor at 521-5243 or dan.taylor@pressdemocrat.com. See his ARTS blog at http://arts. blogs.pressdemocrat.com.)