Yellowstone National Park is waiving admission fees this weekend, the 15th through the 17th, in recognition of the Martin Luther King Jr. holiday on Monday. Fee free entrance:

"Doesn't matter how you care to come to Yellowstone, Saturday, Sunday, Monday, by your personal car, in an RV, by a commercial bus, if you want to come in on a commercially guided snowmobile or snow coach tour, your entrance fee is waived."

Yellowstone Spokesman Al Nash says the fee for a personal vehicle is usually 25 dollars for a seven day pass. And, if you are driving that personal vehicle, you'll have to come in by the north entrance.

One way in for vehicles:

"Access into Yellowstone is a little more challenging this time of year. We only have one entrance where you can drive a wheeled vehicle through; that is our north entrance at Gardiner, Montana, but you can come in through Gardiner to Mammoth Hot Springs and drive all the way out to Cooke City and Silver Gate, Montana, year around."

Mr. Nash said there are snow coach trips that you can book from the north, west and south entrances to the park, in addition to guided snowmobile excursions into the park, but the east entrance only has vendors that offer snowmobile trips.

East entrance snowmobiles:

"If you go to w-w-w-dot-nps-dot-gov-slash-yell, y-e-l-l, you can find a lot about visiting the park any time of the year, and there's actually a list of contact information for those authorized providers of snowmobile and snow coach trips, one stop shopping to find out who from each entrance provides that service."

The entrance fee is separate from the cost of guided excursions into the park. And for those over-snow expeditions, there are services available even deep inside the park. For example, the Old Faithful Snow Lodge is open, with a restaurant and gift shop, and the Old Faithful Visitor Education Center is open throughout the winter season.