If you're thinking of a winter trek to Yellowstone National Park, there are some things you have to accept. One, more than likely it will be cold and snowy. Two, lodging reservations will be tricky, as there are a very limited number of lodges open. Three, it's not going to be cheap. But if you're OK with those three conditions, you'll more than likely have an incredible time.

The winter season in the park is scheduled to open December 18 ... if the weather cooperates. Once winter storms thickly blanket the park's Grand Loop, the park's gates are thrown open to over-snow vehicles, cross-country skiers, and snowshoers.

Now, there are two main ways of visiting Yellowstone in winter. The best is to book a room in the Old Faithful Snow Lodge. A close second is finding a place to stay in West Yellowstone and taking day trips into the park. Other options including staying in Cody and making a trip into the park via snowmobile or snowcoach, or staying at Mammoth Hot Springs just inside the park's north entrance.

Obviously, for the complete Yellowstone-in-winter experience you'll want to stay in the park. Not only do you get to play in the park during the daylight hours without factoring in travel time to your room outside the park, but once nightfall does descend the day trippers exit and it's almost like having Yellowstone to yourself. The biting cold that slips over the park as the sun vanishes seems to make the night sky with its pinholes even more sharp and magnified, and adds to the steaming fury of the geysers.

In the park you have two options (unless you're pitching a tent at the Mammoth Campground, which really shows your mettle!): Book a room at the Old Faithful Snow Lodge or one of its associated cabins, or stay at the Mammoth Hot Springs Hotel. The bonus of staying at Old Faithful is the proximity of the geyser basins and the remote, isolated feeling. The bonus of staying at Mammoth is the road to the Lamar Valley is open, meaning you can drive into the valley to look for wolves and other wildlife. You also can drive to Tower Junction, which is a great jumping-off point for cross-country or snowshoe touring. From either location you have more options of traveling elsewhere in the park, either by snowcoach, snowmobile, cross-country skis, or snowshoes.

Of course, a stay in West Yellowstone has its benefits, too. There are more lodging options that typically will be a little more affordable than a room at Old Faithful. Dining options increase. There's the Grizzly and Wolf Discovery Center that makes spotting grizzlies and wolves a tad easier than doing so in the park. And, if you like to cross-country ski, the Rendezvous Ski Trail System is one of the best in the Rockies.

From West Yellowstone you can take a snowcoach or snowmobile tour into the park, or even ski or snowshoe into the park via the Riverside Trail.

Cody probably is not the best option, as it's 53 miles east of the park. But if you've had your fill of geysers and prefer to explore the rugged eastern side of the park, then Cody can be a great base camp. There you'll find some great lodging and dining as well as the Buffalo Bill Historical Center and its wonderful collection of museums that bring the Old West to life. As for visiting Yellowstone, there are outfitters who will haul you all the way to Old Faithful or drop you off at ski/snowshoe trails and return later in the day to collect you. There also is a cross-country trail network between Cody and Yellowstone to sample, as well.

Whichever option you choose, you likely won't go wrong. One thing you definitely should plan on doing, though, is hiking down a park trail, preferably with snowshoes or skis on your feet. Not only does this get you some great exercise, but go far enough and you'll come close to escaping the throttling snowmobiles and snowcoaches and begin to truly appreciate the silence that the snow-filled backcountry offers. And, that's the best way to spot tracks of the wildlife that stays active in the park during the winter months.

If your heart is set on staying in the park, here are some "Winter Getaway" packages being offered by Yellowstone's lodging and dining concessionaire, Xanterra Parks & Resorts:

Winter Getaway packages are available Jan. 3 through March 6, 2010 at Mammoth Hot Springs and through March 5 at the Snow Lodge.

Each package includes Xanterra’s “Snow Card” good for 10 percent off meals, in-park transportation, tours, ski shop services and select retail items. Rates quoted here are per person, double occupancy, plus tax and utility fee.

“Trail of the Wolf” features guided snowmobiling in the interior of the park and wildlife watching by van in the park's Northern Range. This package includes three nights of lodging at Old Faithful and Mammoth, a round-trip guided snowmobile tour between Old Faithful and Mammoth, a “Wake up to Wildlife” tour of the Lamar Valley, two breakfasts per person, welcome gift, a one-hour hot tub rental, unlimited ice skating and skates and a Snow Card. Rates start at $411 per person for double occupancy for two nights at the Mammoth Hot Springs Hotel and one night at the Old Faithful Snow Lodge. Rates start at $546 per person for double occupancy for two nights at the Old Faithful Snow Lodge and one night at the Mammoth Hot Springs Hotel.

“Frosty Fun at Mammoth.” This package includes a minimum of two nights at the Mammoth Hot Springs Hotel, two breakfasts per person, welcome gift, a one-hour hot tub rental, unlimited ice skating and skates and a Snow Card. Rates start at $134 per person for double occupancy and $217 for single occupancy.

“Frosty Fun at Old Faithful.” This package includes a minimum of two nights of lodging at the Old Faithful Snow Lodge, two breakfasts per person, welcome gift, unlimited ice skating and skates, round-trip snowcoach transportation and Snow Card. Rates start at $295 per person for double occupancy and $439 for single occupancy.

“Nordic Heaven at Mammoth.” This package includes a minimum of two nights of lodging at the Mammoth Hot Springs Hotel, two breakfasts per person, welcome gift, full-day ski rental and one ski shuttle per person, a one-hour hot tub rental, unlimited ice skating and skates and a Snow Card. Rates start at $185 per person for double occupancy and $268 for single occupancy.

“Nordic Heaven at Old Faithful.” This package includes a minimum of two nights of lodging at the Old Faithful Snow Lodge, two breakfasts per person, welcome gift, full-day ski rental, one ski shuttle per person and a round-trip snowcoach tour per person, unlimited ice skating and skates and Snow Card. Rates start at $346 per person for double occupancy and $490 for single occupancy.

Winter rates for single or double occupancy, plus tax, for individual room nights at Mammoth Hot Springs Hotel start at $85 for a room without a private bathroom or $115 for a room with a bathroom. Rates at the Snow Lodge are $191 for a lodge room, $140 for a Western Cabin or $94 for a Frontier Cabin, all with private bathrooms.

Except for the road from Gardiner, Mont. to Cooke City, Mont. via Mammoth Hot Springs, transportation within the park is limited to snowmobiles and enclosed heated snowcoaches during the winter. Snowcoach transportation is available daily to a variety of park locations. Xanterra also offers a variety of half- and full-day snowcoach, ski and snowshoe tours and ski and snowshoe rentals as well as expert instruction and other services.

Yellowstone National Park Lodges and the Yellowstone Association Institute also offer six Lodging & Learning programs combining expert guides, accommodations, transportation and meals.

Winter Getaway packages may be booked by phone by calling (1) 307-344-7311 or toll-free (1) 866-GEYSERLAND (1-866-439-7375). Complete tour details are also available at the web site www.TravelYellowstone.com.

If West Yellowstone sounds interesting, check out the chamber of commerce site with its many lodging, dining, and activity options. As for Cody, here's the site of its chamber of commerce.