Mile 186½ North Dakota South Dakota boundary marker
historic site
- Built
- 1891
- Material
- quartzite
- 4.5 mi off the Native American Scenic BywayNational
| Date | Sunrise | Golden hour | Sunset |
|---|---|---|---|
| March equinox | 07:46 | 19:15 | 19:54 |
| June solstice | 05:52 | 20:50 | 21:37 |
| September equinox | 07:29 | 19:02 | 19:41 |
| December solstice | 08:21 | 16:10 | 17:00 |
Local time (America/Chicago).
45.94347, -100.43091
Elevation 516 m (modelled from terrain)