High on Mount McKinley in the summer of 2003, stuck in a cramped mountaineering tent and waiting out a storm, John Mitchler took out a pencil to write a list. Wind tore into the nylon fabric above his head. The end was coming for Mitchler, he was sure.

"I decided to write a list of all the people I'd climbed with over the years," he said. "McKinley was to be my final mountain."

Mitchler didn't perish on that high Alaskan peak. Indeed, his party soon made the mountain's 20,320-foot summit.

But for the 50-year-old geologist from Golden, Colo., Mount McKinley did signify the end of a personal quest: For more than 20 years, Mitchler had traveled the country climbing peaks and hiking hills to stand at the highest point of elevation in each of the 50 states.

Highpointing, as this state-by-state summit-seeking pursuit is called, has garnered a following of more than 10,000 people, according to Roger Rowlett, chairman of the Highpointers Club, www.highpointers.org, which was founded in 1988. Every state has a highest point of elevation, be it a towering mountain peak or a nondescript knoll in a cornfield. To highpointers, each one of these summits is geographically significant.

"You need advanced mountaineering skills for peaks like Mount Rainier (in Washington state) and McKinley," Rowlett said. "But completing the list also means traveling thousands of miles through obscure parts of the country."

To tick off Florida, for example, highpointers drive to Britton Hill, a meager slope in the Panhandle with an elevation of just 345 feet above sea level. In Illinois, a state of cornfields and prairie, a 1,235-foot rise called Charles Mound is the destination. Rhode Island's Jerimoth Hill tops out at 812 feet above the nearby Atlantic waters.

More than a dozen states, including Kansas, Kentucky and Ohio, have highpoints with road access, letting people essentially drive to the summit. Wyoming's Gannett Peak, in contrast, requires up to 50 miles of roundtrip backcountry hiking in the remote Wind River Mountain Range.

To date, 155 people are on record as having completed all 50 highpoints, according to Rowlett. Roughly 10 new people a year climb their 50th state summit and are added to the Highpointers Club's list of completers. Plaques are awarded.

Wilderness adventure is an obvious allure for highpointers. But the pursuit also attracts goal-motivated individuals who savor keeping a checklist and marking off each highpoint they reach.

"There's something tangible and satisfying about having a list to check off," said Roger Truesdale, a 62-year-old retired physical-education teacher from Bloomington, Minn. He has climbed all 50 highpoints, 49 of them with his wife, Jane.