A Substack investigation reveals that Yemen's listed size of 555,000 sq km originates from a 1991 Statistical Yearbook that incorrectly extended the northern border to the 20th parallel for propaganda purposes. The author replicated borders on Google Maps, arriving at 456,000 km2, noting the discrepancy equals a quarter of the country's total area. While the CIA World Factbook and UN cite 527,968 km2, the author traces this to 1991 editions that summed figures from North and South Yemen.

Further digging shows these historical figures are wildly inaccurate; North Yemen was only 136,000 km2 and South Yemen 288,000 km2. The investigation traces the 195,000 km2 North Yemen figure back to a 1904 Ottoman province measurement repeated uncritically for decades. The author concludes that long-standing geographical data suffers from unchecked repetition of outdated sources.