All the way part of rural Virginia -- an annual three day event brings people from far and -- for free medical care they urgently need. It's a completely volunteer operation people who treat thousands... See More
All the way part of rural Virginia -- an annual three day event brings people from far and -- for free medical care they urgently need. It's a completely volunteer operation people who treat thousands need and sadly demand is growing every year. Here again is ABC's Bob Woodruff. Wise Virginia -- a coal mining -- too far from any major airport. Stan Brock fluid from Knoxville program is based on -- minor -- morning. While Graham has done just over 700 expeditions. Has -- calls the clinics since 1985. This idea came to him when he was injured on a cattle ranch in the Amazon 26 days on foot from the nearest doctor. To help others find -- Brought medical teams to other undeveloped countries like India Haiti. But -- -- quickly learned was that there was desperation in the US as well. Especially in places like lies -- jobs have disappeared and few doctors hang their shingles consists of a one time opportunity. That they know they can afford. To get the care that they need. The -- clinic is one of the largest that they do here in the United States serving some 2500 people. -- on the second morning. Hundreds again lineup in the predawn darkness. For a chance to see a doctor and so the first thing we can do and is bringing the people who were left over -- and waiting here through what that some of -- 24 hours or able. -- among the hundreds streaming in the rain losses who live now waited more than 24 hours. I think we eyes and listen in -- -- -- -- and handling outer bands. But suddenly this man is moved to the front of the line. Robert Ellis has walked fifteen miles through the night walking stick in hand to get here. I had a rap but I -- have -- gas and drove meters in August and October -- -- and small. Even though -- -- just return the day before from serving in Afghanistan. Ellis knew he had to come to wise. And I really need not take things are about and they're really bad and -- here I don't know which -- worse. But his visit to triage uncovers something else. Dental and hearing will have to wait is he is taken to the metal content and cardiology and haven't changed. The clinic offers specialty areas including cardiology dermatology. Orthopedics. Even mobile X ray unit. And sister but paperwork they hear never get -- that we don't -- About eighty dental chairs are up and running sixteen eye examination stations. Two optical labs grinding 600 pairs of glasses a day. Gary about 101000 lives here -- they get all are those volunteers. Whose ranks have grown by one. As Virginia senator Tim -- slips into registration to do his part. By brock's estimation -- is one of only a dozen or so politicians who have ever been to -- of that. People drive -- and then help get here to a traders early to camp and -- in the get care in this the most powerful nation or we can do so much by the afternoon Allison is getting his eyes checked fox. You know what -- -- -- There's been pretty much everything else. Thanks. We'll freshness and here change. I'm only here and agents didn't know -- well here's my god maybe there. And try to get -- this program to. I -- I got to dismiss. On Sunday morning the third and final day the crowd is much small -- to -- today. And so we're bringing in religious an extra hundred people -- vision and an extra hundred people in dental and that you just about doing for the morning. The very last of the dental patients continued to be worked -- equipment is packed up. In the heavens -- We don't need to be doing this -- I would rather be back in -- and India and Africa. And everywhere this organization began in the Amazon -- doing here in the world's richest country. But I -- see this ending anytime soon. The numbers from the weekend support the claim some 12100 dental patients have been seen 4000 teeth pulled. 900 pairs of glasses provided in total over two million dollars worth of health care provided. All free of charge. It just -- matter where you go in the United States can find these huge numbers of people that I did don't have access to care because it's an underserved area. Or most cases in. They simply can't afford to go to -- -- they can't afford your PI -- -- And and so they're going to be relying on the kind of services we provide. For Nightline I'm Bob Woodruff. In wise Virginia. What a remarkable effort. Our thanks to Bob Woodruff for more about remote area medical visit our website at abcnews.com. Slash Nightline.
This transcript has been automatically generated and may not be 100% accurate.