Lisbon
100 km²
San Diego
964 km²
Portugal
United States
Area Comparison
Lisbon is 9.6x smaller than San Diego
Population Comparison
Lisbon has 2.5x fewer people than San Diego
San Diego is significantly larger, covering 9.6 times the area of Lisbon. San Diego spans 964 km² (372 mi²) while Lisbon covers 100 km² (39 mi²) — a difference of 864 km². You could fit Lisbon inside San Diego approximately 9 times.
To put Lisbon's size in perspective, its area of 100 km² is roughly the same size as Paris (city proper). Meanwhile, San Diego at 964 km² is roughly the same size as Berlin.
Lisbon's footprint is roughly about 14,000 American football fields, 50 times the area of Monaco, or 29 times the area of Central Park — pick whichever unit feels intuitive. For San Diego, that's about 135,000 American football fields, 16 times the area of Manhattan, or 9 times the area of Paris.
Lisbon is the capital and most populous city of Portugal, with an estimated population of 575,739 as of 2024, within its administrative limits and 3,028,000 within the metropolis, as of 2025. Lisbon is mainland Europe's westernmost capital city, and the only one along the Atlantic coast, the others being on islands. The city lies in the western portion of the Iberian Peninsula, on the northern shore of the River Tagus.
Known as "City of Seven Hills", Lisbon covers 100 km² with a population of 0.6 million. The city was founded around 1200 BC. Lisbon is known for Belém Tower, Jerónimos Monastery, Tram 28, among other attractions. The city's main transit system is the Lisbon Metro.
Lisbon is mainland Europe's westernmost capital city and the only European capital along the Atlantic coast.
San Diego is a city on the Pacific coast of Southern California, adjacent to the Mexico–United States border. It is the eighth-most populous city in the U.S. and second-most populous city in California with a population of over 1.4 million, while the San Diego metropolitan area with over 3.3 million residents is the 18th-largest metropolitan area in the country. San Diego is the county seat of San Diego County.
Nicknamed "America's Finest City", San Diego has an area of 964 km² and is home to 1.4 million people. It was established in 1769. Visitors come for San Diego Zoo, Balboa Park, Coronado Beach, and much more.
San Diego sits directly on the Mexico-United States border, making it California's southwesternmost major city.
Lisbon has a population density of 5,500 people per km² — a densely populated city. San Diego, with 1,442 people per km², is a relatively spread-out city. Lisbon is dramatically more crowded, with 3.8x the population density.
Size Ratio
Lisbon fits inside San Diego ~9 times
Density Gap
Lisbon is 3.8x more densely populated
History
Lisbon is ~2,969 years older
Lisbon covers 100 km². Cities with a similar urban footprint include Barcelona (101 km²), Paris (105 km²), Copenhagen (91 km²), Zurich (88 km²), or Vancouver (115 km²).
San Diego covers 964 km². Cities with a similar urban footprint include Abu Dhabi (972 km²), Dallas (997 km²), Berlin (892 km²), Santiago (838 km²), or Hong Kong (1,114 km²).
The straight-line distance from Lisbon to San Diego is 9,145 km (5,682 miles), with an estimated flight time of ~11h 16m.
Want to explore more? Compare city sizes for any two cities worldwide, or share your location live with friends.