Along with visiting the 16 extreme compass points, I'm also visiting several other extreme geographic places during my road trip. Here are the other extreme places I've visited so far.  These are shown on my accompanying map:

Washington

Oregon

California

Arizona

New Mexico

Texas

Oklahoma

Colorado

  • Highest city in the United States
  • Highest airfield in the United States
  • Highest county, by average elevation, in the United States
  • Most remote county (fewest roads per sq. mile) in the contiguous United States
  • Coldest city in the contiguous United States
  • Headwaters of the Rio Grande River
  • Lowest 14,000-foot peak in the U.S.
  • Highest state, by average elevation, in the United States
    • Colorado:  6,800'
    • Coming soon  |  See Google Map
  • Lowest point in the highest state
    • The Arikaree River on the Colorado/Kansas border
    • Coming soon  |  See Google Map
  • Tri-State Marker
    • Colorado, Nebraska, and Kansas boundary (near Wray, CO)
    • Coming soon  |  See Google Map

Utah

  • Four Corners
    • The only point common to four states (Utah, Colorado, Arizona and New Mexico)
    • Coming soon  |  See Google Map

Montana

  • Marker for the 45th Parallel:  Halfway between the equator and the North Pole
    • Clark Canyon Reservoir dam
    • Coming soon  |  See Google Map
  • Headwaters of the Missouri River
    • Trail Creek, near Lemhi Pass
    • Coming soon  |  See Google Map

Kansas

  • Geographic center of the contiguous United States
    • Near Lebanon, KS
    • Coming soon  |  See Google Map

South Dakota

  • U.S. "Pole of Inaccessibility" (the farthest point from any ocean coastline
  • Geographic center of the 50 states
    • Near Belle Fourche, SD
    • Coming soon  |  See Google Map

North Dakota

  • Highest point in North Dakota
    • White Butte, 3,506':  near Bowman, ND
    • Coming soon  |  See Google Map
  • Geographic center of North America

Minnesota

  • Coldest city in the contiguous United States
    • International Falls, MN (or Gunnison, CO)
    • Coming soon  |  See Google Map
  • Headwaters of the Mississippi River
    • Lake Itasca, MN
    • Coming soon  |  See Google Map
  • Marker for the 45th Parallel:  Halfway between the equator and the North Pole
    • Minneapolis, MN
    • Coming soon  |  See Google Map

New Hampshire

  • Highest point in the northeastern United States
    • Mt. Washington (6,288')
    • Coming soon  |  See Google Map

Maine

  • Highest point in Maine
    • Mt. Katahdin (5,267')
    • Coming soon  |  See Google Map
  • Marker for the 45th Parallel:  Halfway between the equator and the North Pole
  • Easternmost city in the United States