Sunday, September 30, 2007; P04

The well-maintained Corridor trails (Bright Angel and the South and North Kaibab paths) are the main arteries across the canyon. No permits are needed for day hikes; one is required for overnight use of the back country ($10), though Phantom Ranch guests don't need one. Hiking is permitted year-round, though facilities on the North Rim are generally closed from mid-October to mid-May.

GETTING THERE: Depending on whether they start from the North or South rim, most hikers fly into either Las Vegas, Phoenix or Flagstaff and rent a car. Fares from the Washington area to Phoenix and Vegas start at about $200 round trip, and about double that to Flagstaff. The entrance fee to the park is $25 per car.

WHERE TO STAY: There are plenty of choices both inside and outside the park on the South Rim, but if you're going in peak season, plan well in advance. Our party of four stayed on the South Rim in a cabin at the park's Bright Angel Lodge ($89 a night double), where connecting rooms included TVs, ceiling fans and fridges. On the North Rim, the only in-park choice besides camping is the lovely Grand Canyon Lodge; our two-room cabin ($106 for four) had a shared bath, comfortable beds and little else.

Guests at Phantom Ranch, at the base of the canyon, stay in either cabins (included in overnight mule trips; rates per cabin for non-mule riders start at $92.86 double) or the men's and women's dorms ($34.16 per person per night). Children are welcome in the dorms. Dorms have five sets of bunk beds and a shared bath. They're primitive but well air-conditioned and the beds are comfortable. Beware of the 4:30 a.m. wake-up call.

Reservations number for all park lodging: 888-297-2757. On the Web: South Rim, http://www.grandcanyonlodges.com; North Rim, http://www.grandcanyonnorthrim.com; and Phantom Ranch, http://www.grandcanyonlodges.com/Phantom-Ranch-704.html.

WHAT TO EAT: While there are restaurants and snack bars on both rims, there's only one place to nosh at Phantom Ranch, and you must reserve before you arrive. All meals are all-you-can-eat and family-style, including iced tea; save room for the great slabs o' chocolate cake. Breakfast is $17.50 per person, steak dinners are $35.61, veggie and stew dinners $22.60. Sack lunches are $10.14 per person. Beer, wine and soft drinks available most of the day.

INFORMATION: Grand Canyon National Park,928-638-7888, http://www.nps.gov/grca. -- J.D.

Tips for Hiking the Canyon Rim to Rim

Sunday, September 30, 2007; P04

* Watch your timing. We hiked rim to rim in late August when it's brutally hot -- but only because our preferred dates in September were sold out and that's what our schedules dictated. Winter can be cold and snowy. The best times are generally late spring and early to mid-autumn, though the North Rim facilities are closed from mid-October to mid-May.

* Get the right gear. Your hiking shoes or boots, of course, are of utmost importance and should be well worn in (and should allow some space for your feet to swell). Test your backpack to make sure it's comfortable. Get a walking pole or, even better, poles. Dress in layers (there can be as much as a 20- to 30-degree difference in temperature from the rims down to the Colorado River) and recycled clothing -- no one is going to care how you look at Phantom Ranch.

For a guide to gear and tons of other info, check out Hitthetrail.com (http://www.hitthetrail.com), a superb Web site maintained by Denise Traver, a former park ranger and backpacking field guide.

* Get in shape. Hundreds of hikers are rescued each year from the Grand Canyon, many because they underestimated its rigors and overestimated their own ability. Hitthetrail.com suggests, among other things, to run "up and down bleachers, subways, or stairways. It's even better if you wear a backpack carrying some substantial weight inside -- perhaps a bag of dog food or kitty litter."

John Annerino's exhaustive "Hiking the Grand Canyon" (Sierra Club Books) also has good info on how to prepare physically -- and mentally -- for the trek, as well as extensive details on the trails and a guide on prepping for such dangers as flash floods.

* Know who's boss. When it's hot, take extra precautions (take frequent breaks, carry and drink plenty of water, wet down your shirt and hat, etc.), and if you can, hike in the early morning and late afternoon, when it's cooler. Eat plenty of salty food to compensate for heavy sweating. Go to the backcountry primer on the Grand Canyon National Park's Web site (http://www.nps.gov/grca/planyourvisit/backcountry.htm) for more details, and pick up the guides available at park entrances for trail info.

Remember that the mules have priority on the trails (for info on booking a mule trip from either rim, go tohttp://www.nps.gov/grca/planyourvisit/mule_trips.htm). If you see them coming, step off the trail on the uphill side away from the edge, stay quiet and wait until the last mule is 50 feet away to resume hiking. Then hold your nose.

* Reserve in advance. Phantom Ranch fills fast, and choice lodging on the rims can book months ahead of time. Don't show up without reservations during peak travel times. (See Details on how to book.)

* Don't forget your rental car. You could, as Grandcanyonhiker.com (http://www.grandcanyonhiker.com) suggests, hike rim to rim to rim to get back to your car. We took the Trans-Canyon Shuttle (928-638- 2820), which runs between the rims May 15-Oct. 15; fare is $70 per person one way.

* Enjoy! As the hiking gets more difficult, it's natural to just want it to end. But take frequent breaks, revel in your surroundings and take lots of pictures. You'll regret it if you don't.

-- J.D.