The American bison, or buffalo as it's known to most people, once roamed the North American continent from Canada to Mexico and from the western Great Plains to the east coast. Their numbers were so great that a 19th century pioneer claimed you could stand in one spot from morning till night and a single herd would still not have finished passing in front of you. By the start of the 20th century, though, you could stand in the same spot all day and not see any buffalo at all.

But 100 years later, their population has rebounded from the wholesale slaughter of America's westward expansion, and once again you can stand in one spot in South Dakota and see these massive symbols of the American frontier.

As mountain snows melt into the running waters of South Dakota's Black Hills, Custer State Park's buffalo herd moves from its wooded winter retreat on to the open prairie. Spring marks their return to the grasslands and the start of calving season, when cows will bear their young.

Spring is also the start of tourist season and by summer, thousands of visitors have spent endless hours traveling the huge park with one goal: to see buffalo. Bilma Lewis Uehara, 10, is on a family vacation from his home in Japan. "There's no buffaloes in Japan, so I thought I wanted to see a buffalo," he says. "The whole time in the car I've been saying, where's the buffalo?"

His mother, Amy Klemke Uehara, is an American from Denver, Colorado. She's lived in Japan for 17 years and says she makes it a point to come to the park whenever she's back in the States. "I feel like I haven't seen America until I've seen the buffalo, really," she says. "I have a buffalo poster... ah, I show the kids. And my family's from this area, Wyoming, Nebraska, Colorado. Buffalo feels like home, somehow. I don't really feel like I'm home until I come out here, I guess."

Mrs. Uehara isn't alone in her feelings for the majestic creatures that once roamed the Great Plains in vast herds. Even park superintendent Rolly Noem says he and his staff don't take the animals for granted. "They are so symbolic of this country that to be able to see them in a natural setting, in a natural environment to me is such an exciting opportunity and even though that's a common sight for us in the park, it's still a thrill to see that whenever we have the opportunity as well," he says.

Some 150 years ago, white settlers, commercial hide hunters and thrill-seekers flooded the Plains, killing millions of buffalo. In just 50 years, from 1835 to 1885, the buffalo population was reduced from more than 40 million to less than 600 animals. Their loss was felt most keenly by American Indians, who relied on the animal for everything from food and tools to clothing and shelter.

John Black Feather, a member of the Lakota tribe, now raises buffalo on South Dakota's Pine Ridge Reservation. He recalls, "Back in the old days, the buffalo really took care of our ancestors because of the bones that they used to make a few things and the hide was for clothing and tipis. Of course, me living in a modern world, I don't depend on buffaloes a hundred percent, but looking back at what buffalo did for my ancestors, I appreciate that." The resurgence of the buffalo from near extinction to its present population of some 250,000 is one of the greatest success stories of the modern American West. The pages of that story were written by conservationists, private ranchers and state and federal agencies determined to protect the buffalo and return it to its natural habitat.

As her family watches the Custer Park herd graze, Mrs. Uehara says she thinks the growing herds represent this country better than more famous symbols, like Disneyland or New York City. "I think that's just amazing, that America's come a long way [from] thinking it can just wipe things out without caring. And then take the time to restore something that really symbolizes America," she says. "I'd like other people in the world to see a buffalo when they come through."

Others from around the world have come to see the buffalo. Irvin de Lumbarda, of Belgium, is sitting in his van within 15 meters of most of the park's 1,500-head herd. These animals are his primary reason for being in the park. "I think, years ago when ... in the time of Buffalo Bill when there were perhaps thousands and thousands ... it must be, very great thing to see that. You have to come here to see it with your own eyes. It's strange to see them so close," he said. "You can nearly touch them but, uh, stay away - they are really wild."

A recent rare tragedy in the Park occurred this year when a man wandered too close to a 900-kilo bull and was gored to death. Linda Stole, of nearby Wind Cave National Park, stresses it's important for all visitors to remember they're dealing with wild animals. "We're not a petting zoo, so we encourage them to observe the wildlife from a distance. And by and large, so far, they do that," she says. "Although every now and again you'll see someone walking across the prairie where they'll see a bull standing to get a closer picture. That's not a very wise idea."

But these majestic symbols of the American West can be seen and admired from a safe distance. And visitor Amy Klemke Uehara believes that's the way it should be. "A buffalo might be quiet, but it's volatile," she says. "It's majestic and people should be in awe of it. It's not something to take lightly. It's... revered. I think of words like that. Being in awe, revering it, respecting it. "