For $25, you can drive into Yellowstone or Yosemite national parks, your car loaded with family, and spend the rest of the week exploring. At Mesa Verde National Park, the park's entrance fee is $15 per vehicle, but experiencing this incredible park can become much more costly much more quickly.

For instance, if you want to go off the well-worn path and explore some cliff dwellings that are not normally open, you'll need to pay $25 for that experience. And $25 for your spouse, and $25 each for any children who tag along on the two-hour ranger-led hike to either Mug House or Square Tower House. So if you brought along your spouse and two kids, it'll cost $100 for your entire family to visit those intriguing cliff dwellings.

That $25 per person fee is more than eight times the $3 you pay to join rangers in climbing a ladder up into Balcony House, walking through Cliff Palace, or to ride a tram to Long House so you can climb up its ladders and gaze into its kivas.

And yet, according to Park Service officials, that $25 fee is, at best, a break-even proposition to cover the costs the park incurs to make tours of Mug House and Square Tower House possible.

"The special tours that you referenced in your question are limited both in availability and capacity and, short of heavily subsidizing these tours with park base funds, we choose instead to charge a price that will generate adequate income to match our tour expenses," John Wessels, the director of the Park Service's Intermountain regional office told me when I asked about the fee.

Going Into The Attic

Though Mesa Verde has 600 cliff dwellings, visitors have largely been limited to touring Balcony House, Spruce Tree House, and Cliff Palace atop Chapin Mesa. Some exceptions have cropped up in recent years, as the Park Service looked for ways to bring small groups of visitors to some other sites, such as Mug House and Square Tower House. (For details of this summer's tours, click here.)

This is the third summer for these special tours, which, in a sense, are not unlike going up into your attic and dusting off long-forgotten treasures from the past. And really, it's both amazing and unfortunate that while there are hundreds of cliff dwellings within Mesa Verde's boundaries, just five -- Cliff Palace, Balcony House, Spruce House, Long House and Step House -- have been open on a regular basis for visitors.

Maps of the mesas included within the national park's boundaries are dotted with ruins -- Double House, Sun Point Pueblo, Square Tower House, Sun Temple, Fire Temple, Cedar Tree House, Kodak House, and Jug House. And those are just the ones with names. There also are sites denoted simply by numbers -- 1644, 1645, 1676, 1452, 1801, 1291, and 1595 just to name a few.

The problem of opening more than the five named above to the public, of course, has been a lack of money and manpower. Money to both stabilize ruins enough so they can be toured, and manpower to provide the tours and perform the ongoing stabilization work. And then, too, there's the issue of access. Some sites are just too remote and difficult to reach to make public tours realistic. And that's unfortunate.

A visit to Mesa Verde provides keen insights into how the ancestral Puebloans lived; how they built their homes high in alcoves for protection and yet farmed on the surrounding plateaus, for instance. In some cases they would climb down to the canyon floor and then go up the other canyon wall to reach their gardens. They also were masters at irrigating their gardens, and remnants of check dams can still be found on Wetherill Mesa.

Folks who can afford the short hike to visit Mug House won't be disappointed. While the park's main dwellings that are accessible to visitors have been restored, Mug House has had only minor stabilization work done to it down through the decades. That much of the complex is still intact after all these centuries is a testament to the building skills of the ancestral Puebloans.

Mug House was named for several mugs that were found tied together when the five Wetherill brothers, who pioneered much of the initial archaeological work at Mesa Verde in the late 19th century, and Charles Mason, a brother-in-law, ventured into the dwelling around 1890.

"It appeared as though the people had been frightened away with no opportunity to carry anything with them," Mr. Mason went on to note in his observations. "All seemed to have been left just where it had been used last. No house in Mesa Verde yielded so much in proportion to size."

Today the mugs are gone from the dwelling, of course, but you still can peer into the kivas and rooms, see the smoke stains that cling to the sandstone alcove ceilings, gaze out over Rock Canyon, and simply stand in the quiet envisioning the sounds of laughing children and adults at work building fires or making pottery.

How Park Officials Arrived At That $25 Ticket Price

The $25 ticket price, park officials explained to me, is necessary to cover an array of expenses they incur in temporarily opening these sites.

Square Tower House. Kurt Repanshek photo.

For instance, along with the ranger(s) needed to lead these treks, the park assigns at least two archaeologists to visit the sites at the start of the season to ensure visitor and site safety, and then again one or two times a month to assess any impacts. A natural resource employee also is sent to the sites to mark any endangered plants so they aren't trampled, and this individual also returns once or twice a month to determine if there have been any impacts from the special tours. In addition, two workers from the park's stabilization crew check the sites before the season to make sure they're safe for visitors, and then at least four members of the trails crew must go out to make any needed trail repairs, mark the end of the trail so visitors don't go farther than they should, and to ensure the trails are ready for traffic. At season's end these staff return to the sites to ready them for winter.

In all, explained Betty Lieurance, the park's administrative assistant, 402 hours of staff time are required each year to make these tours possible. As the average wage of these employees is $22.35 per hour, with benefits pushing that to $27.12, the tours' cost to the park is nearly $11,000.

"The price of the ticket is based on 70 percent sale of the tickets because the tours still go whether or not they are full. Based on 70 percent, we would take in $12,950," Ms. Lieurance said.

Add in the cost of vehicles and gas to get the visitors to the trails leading to the ruins, and the $3 per ticket the park pays the company that runs the ticket reservation system, and the park breaks even, at best, on the costs of offering these tours, she explained.

While all tours at Mesa Verde generated $775,000 last year, costs for running those tours amounted to $756,000. The remaining $19,000 was returned to the U.S. Treasury. While that $19,000 theoretically could have gone to reducing that $25 ticket price, by law the park is required to return at season's end any surplus revenues it might take in from all ticketed tours. Trying to guesstimate at the start of a season whether a surplus might arise at the end of the season is difficult at best.

"If we spend more than we take in, that money comes out of our base and may cut in to other park programs," Ms. Lieurance said. "If we spend less than we take in, we return it to the Department of Treasury in Washington D.C. As you can see, it is a gamble, since we have no way of knowing how many tickets will be sold or if we will be able to cover our costs."

There seemingly is little question that parks are strapped for operating funds, and have to try to cover their costs when offering some programs, particularly special programs such as the tours to Mug House and Square Tower House. Gamble that it might be, it's unfortunate that Mesa Verde can't retain any surplus ticket revenues at season's end to help offset the costs of these special tours the following year, for visiting these sites is a great experience.