While still an undergraduate at Michigan, I read a newspaper article about a group called the
Extra Miler Club. For the most part, the club's members share the same goal, visit once in their lifetime each county in the United States. In the summer of 2000, with my first real solo excursion, a daytrip from Niles, Michigan to Turkey Run State Park in Parke County, Indiana, I started to keep track of the counties I entered and, in 2004, joined the club. Since that initial trip, I have tallied 689 counties, in 35 states, against a goal of 3,141. I could add at least 202 more counties to my total by including ones visited prior to 2000, but for now, I've left as my goal to re-enter each. With the exception of counties passed through on a cross-country train trip in 1992 and a few counties in upstate New York, I do believe I've identified every eligible county.

[Click on map for full-size pdf of the country. 1MB]
I do not recognize an airport layover, as sufficient to record a county, which only deprives me of a few counties. Any guesses on which ones? Though I'm only about fifth of the way to completion, I have obtained one of the universally-recognized most-difficult counties, Kalawao in Hawaii. Situated on the north shore of Molokai, it is the legal jurisdiction for the famous Kalaupapa leprosy settlement. Today, it is accessible to the public only by mule or plane. I utilized the former transport mode.
So far, I've finished five states—Connecticut, Delaware, Hawaii, Rhode Island, and Pennsylvania—with designs to complete New Jersey and Maryland this year.