Visiting Every City in the World: Theoretical but Impractical

With over 40,000 cities globally (UN defines ~10,000 as "urban agglomerations" >300k; many more smaller), visiting every one is theoretically possible but practically impossible for a single human.

Barriers

• Time: At 1 day/city = 110+ years nonstop. Realistically: transit, visas, rest = lifetimes.
• Cost: Flights, visas, accommodation, food = millions of USD.
• Access: Closed cities (military, scientific), conflict zones (Syria, Yemen, Myanmar), remote islands (Pitcairn, Tristan da Cunha), North Korea (restricted).
• Visa/Political: Passport power determines access; some countries deny entry based on nationality, travel history.
• Health/Safety: Disease, crime, infrastructure gaps.
• Definition: "City" thresholds vary by country (200 in Denmark, 50,000 in Japan).

Notable Attempts

• Alberto Cairo (data journalist): ~1,000 cities.
• Doug Lansky (travel writer): 180+ countries.
• Guinness World Records: "Most UNESCO sites visited" (not cities).

Meaningful Alternative

Focus on depth over breadth: immerse in regions, learn languages, build relationships. The "city count" metric is arbitrary; transformative travel comes from connection, not checklists.