As winter descends on the Pacific Northwest and drapes its high country under a thick blanket of snow, many hikers tuck their boots away, content to sit out the rest of the season until the late spring sun melts out the alpine trails once again.

But many of the region's more dedicated hikers know there's another option. Head for the lowland valleys,many of which stay green and snow-free all year thanks to the area's temperate temperature climate.

There are a handful of lowland trails within easy reach, providing access to lush, moss-draped forests and tumbling rivers, even in the depths of winter.

"There are really no busy trails this time of year," said Dan Nelson of the Washington Trails Association. "It's a great time to be out exploring and to find some solitude."

Sure. It rains a lot, but it's also the moody, misty weather that nourishes the Pacific Northwest's grand cathedral-like forests. And as long as you're outfitted for cool, damp and sometimes muddy trails, you can easily keep your boots out and hiking legs working year round.

"Hikers will definitely want to be prepared for shorter days, colder temperatures and wet conditions," Nelson said. "Storms can blow up fast this time of year."

With a little extra gear stuffed in your pack to prepare for nasty weather, set out and explore these three lowland trails. They're all close by and among the best winter hikes the Cascades have to offer.

Boulder River

North of Everett and east of Arlington you'll find the Boulder River Wilderness Area and the Boulder River Trail. The trail plunges hikers into one of the last remaining old-growth forests in the low valleys of Western Washington, gently rolling and always within earshot of the tumbling river below. Here, the dense, green canopy of trees overhead will soften downpours on even the stormiest of days.

The trails's best landmarks are two waterfalls, one at 1 1/4 miles and the other a quarter-mile beyond. Side trails lead down to the waterfalls, where you can sit and watch ribbons of water fed by winter rains noisily tumble down steep cliffs to the river below. The waterfalls themselves make good destinations, or you're free to wander the trail to its end, a total of about 4.5 miles.

To get there: Reach the Boulder River Trail by driving Highway 530 east from Arlington. at 19.8 miles, turn right on U.S. Forest Service Road 2010. Drive the unpaved road to the end.

Robe Canyon

For rails-to-trails fans, the Old Robe Canyon Historic Trail, along Snohomish County's scenic Mountain Loop Highway, offers access to a rich slice of history, passing through a scenic canyon along the Stillaguamish River.

The trail follows the route of an old railroad line that once connected the mountain gold mining town of Monte Cristo with smelters along Puget Sound. Today, as you walk along the quiet former railroad bed, in places hammered into the bedrock and perched above the thundering water, you may be amazed that a train could navigate such precipitous terrain.

Hikers will find a wonderland of mosey trees and swirling water in the rugged depths of the canyon. Although not an overly long hike at under two miles, you'll find plenty of distractions along the way by watching the river's rapids crashing against giant boulders, or stopping to admire the two cavernous railroad tunnels carved from the rock with hand tools.

Although the grade is gentle, walk with caution --- the trail is narrow and footing poor in spots, particularly in wet weather. And although a footpath continues on through the canyon after the trail's end, it's hazardous going.

To get there: Go to Robe Canyon by driving the Mountain Loop Highway trailhead on the right side of the road along with a small turnout for parking.

For more information, the Outdoors Recreation Information Center, located in Seattle's REI store, provides information on hikes and trail conditions. There are also a number of local hiking books and Web sites providing helpful information.

Snowqualmie River's Middle Fork Trail

Just over one-hour drive from downtown Everett is the Middle Fork Trail, one of the region's best winter hikes, following the swift, turquoise waters of the Middle Fork of the Snoqualmie River.

The Middle Fork valley is a true gem for winter hikers, offering spectacular mountain peaks, a wild river and extensive old-growth forests. "If the valley were next to any other major U.S. city, it would have long ago been designated a national park," said Rick McGuire, president of the Alpine Lakes Protection Society.

The Middle Fork Trail, the main year-round trail in the valley, is a great walk for families and beginning hikers. Starting at a gracefully arching wood bridge over the river, the trail meanders for more than 12 miles, its gentle grade offering the option for either a short walk or long trek. Along the trail you'll pass moss-covered maples and groves of giant cedar and Douglas fir trees. Stop at the river's edge to contemplate the swirling rapids, or to stare across at the jagged, snow-dusted summit of Garfield Mountain. Expect some mud in winter. And although the U.S. Forest Service has closed the trail to bikes, you're likely to encounter a few defiant mountain bikers.

To get there: Drive I-90 east from Seattle to Exit 34. Turn left under the freeway and right on the Middle Fork Road, a partially paved, partially dirt road. In about 11.5 miles you'll find a large parking lot and the trailhead on your right.

 Dave Wortman is a free-lance writer based in Seattle. He can be reached at dewortman@earthlink.net.