- Platonic solid (Wikipedia)
In geometry, a Platonic solid is a convex, regular polyhedron in three-dimensional Euclidean space. Being a regular polyhedron means that the faces are congruent (identical in shape and size) regular polygons (all angles congruent and all edges congruent), and the same number of faces meet at each vertex.
- Washington State Route 539 (Wikipedia)
State Route 539 (SR 539, named the Guide Meridian) is a north–south state highway in the U.S. state of Washington. The highway travels through northwestern Whatcom County and connects Interstate 5 (I-5) in Bellingham with Lynden and the Canadian border near Langley, British Columbia.
Mount Baker, WA simplified hazards map (usgs.gov)