Venice Italy

Venice — built on 118 small islands in a lagoon in northeastern Italy, connected by 400 bridges and navigated by gondola, vaporetto, and water taxi rather than car — is the world's most unlikely and most beautiful city. Founded by refugees fleeing Attila the Hun and Visigoths in the 5th century CE, Venice grew into the dominant maritime power of the Mediterranean (the Serenissima, the Most Serene Republic, lasted 1,100 years — from 697 to 1797, when Napoleon conquered it), controlling trade routes and accumulating art, architecture, and wealth. Venice's architecture (the Doge's Palace, the Basilica di San Marco with its Byzantine mosaics, the Rialto Bridge, the Grand Canal's Baroque palaces) is built on millions of wooden pilings driven into the lagoon clay — an engineering marvel. The city is slowly sinking (1-2mm/year from groundwater extraction and natural compaction) while sea levels rise — acqua alta (high water flooding) now occurs 100+ times per year, up from 10 times in 1900. MOSE (Modulo Sperimentale Elettromeccanico) — a $6.5B system of floodgates installed at the lagoon entrances — has been operational since 2020 to protect the city.