Kings Canyon or Yellowstone?

Neither is a place to swim, but the water you can actually use differs. In Kings Canyon it is the late-summer river pools such as Muir Rock at Cedar Grove, plus the small sandy shore at Hume Lake, the one spot where you can sit by calm water. In Yellowstone the lake stays near 10°C even in August, the thermal pools are scalding and off limits, and a cold plunge in the Firehole River canyon is about all there is unless you head for a hotel pool.

Yellowstone gives you more to eat, and more that tastes of the region. The historic lodge dining rooms are inside the park, and the gateway towns add steakhouses, brewpubs, bison burgers, trout and huckleberry pie, with Jackson and Bozeman serving the most serious cooking in the area.

Kings Canyon is plainer still: a lodge grill and small market at Grant Grove and at Cedar Grove, and a snack bar at Hume Lake. Most people cook at camp, and the varied Mexican, Hmong and Armenian cooking of Fresno is more than an hour down a winding road.

Yellowstone has real heritage to visit as the world's first national park. The Old Faithful Inn's huge log lobby, the Lake Hotel, the Roosevelt Arch and the stone buildings of Fort Yellowstone are sights in their own right, and the Buffalo Bill Center of the West in Cody adds a major museum of Plains Indian cultures and Western art.

Kings Canyon offers much less. The General Grant Tree, the Nation's Christmas Tree, is the one notable landmark, along with a couple of old cabins, the Big Stump logging area and the visitor centre at Grant Grove.

Both go dark early, so choose on the kind of evening you want. Kings Canyon gives you a campfire under the sequoias, river sound at Cedar Grove and an exceptionally dark sky, with a drink only alongside dinner at a lodge. Yellowstone has a lodge lounge and a few saloons in the gateway towns, but the dawn wildlife watching in Lamar and Hayden valleys sends most people to bed soon after dark.

These are two of the great American wild places, and Yellowstone comes out slightly ahead for the sheer range it packs in. Its volcanic plateau holds most of the world's active geysers, Grand Prismatic Spring, the Mammoth terraces and the yellow canyon at Lower Falls, and the wildlife is just as strong, with wolves and grizzlies in Lamar Valley and bison herds in Hayden.

Kings Canyon is a different kind of landscape: giant sequoias at Grant Grove, a granite valley with walls thousands of metres high and easy walks to Zumwalt Meadow and Roaring River Falls. Beyond the road's end the High Sierra trails, including the John Muir Trail, cross passes above 3,500m.

Yellowstone has more to drive out to, even if each outing is a long day. Jackson's town square and wildlife art museum, Buffalo Bill's Cody, the gold-rush ghost towns of Virginia City and Nevada City, and the high Beartooth Highway to Red Lodge give real alternatives depending on which entrance you use.

From Kings Canyon the list is short: the hand-dug Forestiere Underground Gardens in Fresno and an afternoon among the galleries of Three Rivers. Yosemite is too far for a comfortable day out.

Yellowstone holds children's attention better. Geysers that erupt on cue, belching mud pots, bison beside the road and the bears and wolves at the West Yellowstone wildlife centre make each day feel like an event. The cost is long hours in the car, full summer car parks and constant watching around the thermal areas and the animals.

Kings Canyon works mainly for families who camp. The paved loop round the General Grant Tree and the Zumwalt Meadow boardwalk are easy, but the twisting canyon drive is hard on carsick children and the fast, cold Kings River needs keeping well away from.

Both need a car and neither has public transport, but the driving is shaped differently. Kings Canyon is one long out-and-back: about an hour and a half from Fresno to Grant Grove, then an hour of switchbacks down to Cedar Grove, where trailheads are a walk from camp.

Yellowstone spreads its sights round the 230km Grand Loop, so moving between the geyser basins, the canyon and Lamar Valley takes hours, slowed by bison on the road and full car parks. Both close largely to cars in winter, with Yellowstone's interior then open only by snowcoach or snowmobile tour.

Neither is a shopping trip, though Yellowstone's gateway towns give a little more. Cody and Jackson have Western wear, cowboy boots, hats and galleries selling wildlife painting and bronzes, and West Yellowstone and Gardiner stock fly-fishing and outdoor gear. Kings Canyon stops at the visitor-centre bookshop, sequoia souvenirs and the firewood and groceries of the camp markets.

Kings Canyon is the easier place to keep costs down. Camping is cheap, one pass also covers Sequoia National Park, and staying in Fresno or Visalia is an option if you accept the drive, although rooms and meals inside the park are poor value.

Yellowstone in summer is expensive, with lodge and motel rooms priced well above their comfort, a captive market for food and fuel, and Jackson among the dearest small towns in the country. Camping, picnics and visiting in spring or autumn help a good deal.

Yellowstone has at least a little to watch. The summer rodeo in Cody runs most evenings, West Yellowstone puts on family musicals, and the Grand Teton Music Festival brings a professional orchestra to Teton Village for a summer classical season. In Kings Canyon the only programme is a ranger talk on bears or night skies at a campground amphitheatre.

Yellowstone has the edge if you want to soak. The thermal water inside the park is off limits, but developed hot-spring pools near Gardiner and in Paradise Valley make a slow evening after a day on the loop, and September and October bring calm back to the lake shore.

Kings Canyon offers stillness and nothing more: cool mornings among the sequoias, almost no phone signal and the river at Cedar Grove after dark. There are no spas, baths or hot springs within easy reach.