Parallel Lines: When Latitude Becomes a Border
@chriswhong
Make your own map →Lines of latitude are imaginary, but around the world people have turned them into real borders: ceasefire lines, colonial treaty lines, and state boundaries. This map shows 20+ places where a parallel became (or nearly became) a line on the ground. Hover over a line to see its name, and click it for its story and a link to read more.
A recurring theme: the line on the ground often isn't quite on the parallel. Old surveys missed (Tennessee–Georgia), and ceasefire lines followed the front rather than the latitude (the Korean DMZ).
Part of the #30DayMapChallenge, Day 2: Lines.
Researched and drafted with the help of Claude (Anthropic), then finished by hand in squidmaps. Line extents are simplified and approximate; they show where each parallel serves as a boundary, not survey-grade border data.
Sources
- Wikipedia articles linked in each line's popup
- Iraqi no-fly zones conflict and UN document S/2000/504 (36°N / 32°N / 33°N no-fly zones)
- Morocco–Western Sahara border and US Dept. of State Bulletin 38 (27°40′N)
- Georgia General Assembly HR 4 (2013–14) (35th parallel survey dispute)
- Barwon River and Mungindi (29°S Queensland–NSW border)
Parallel boundaries
- War, ceasefire & partition lines
- Colonial & treaty lines
- North American state/province lines
- Australian state lines
- Approximate or historical
Parallel boundaries
- War, ceasefire & partition lines
- Colonial & treaty lines
- North American state/province lines
- Australian state lines
- Approximate or historical