Most cities sit comfortably above the ocean. But a remarkable number of the world's great urban areas lie below sea level — protected from flooding only by dikes, pumps, storm barriers, and centuries of engineering ingenuity. From the Caspian shores of Baku to the Mississippi delta of New Orleans and the polders of the Netherlands, these cities offer a fascinating window into humanity's ability to inhabit impossible places.
Elevation cross-section — bars not to full scale
Major Cities and Regions Below Sea Level
| City / Region | Country | Elevation | Flood Risk |
|---|---|---|---|
| Baku (city center) | Azerbaijan | −28 m (−92 ft) | Low (Caspian coast) |
| Dead Sea (Jericho area) | Palestine / Jordan / Israel | −430 m (−1,411 ft) | Low (desert basin) |
| Amsterdam | Netherlands | −2 m (−7 ft) | High (dike-protected) |
| Rotterdam (parts) | Netherlands | −1 m (−3 ft) | High (storm barrier) |
| New Orleans | USA | −1.8 m (−6 ft) | High (levee system) |
| Sacramento (parts) | USA | −1 m | Medium |
| Miami Beach (parts) | USA | 0 – +1 m | High (sea level rise) |
| Jakarta (north) | Indonesia | −1 to −4 m | High (sinking rapidly) |
| Tokyo (Kōtō ward) | Japan | −2 m | High (super levees) |
| Bangkok (east) | Thailand | 0 – +1 m | High (sinking at 2 cm/yr) |
| Venice | Italy | 0 – +1 m | High (MOSE barriers) |
| Dhaka (parts) | Bangladesh | 0 – +2 m | High (monsoon floods) |
Baku: The World's Lowest Capital City
Baku, the capital of Azerbaijan, holds the unusual distinction of being the world's lowest-lying capital city at −28 meters (92 ft) below sea level. Baku sits on the southern shore of the Caspian Sea — the world's largest landlocked body of water, which itself lies 28 m below the global ocean sea level. This means Baku's waterfront is genuinely below where the ocean would be if connected.
Despite its sub-sea-level position, Baku faces relatively limited flooding risk because the Caspian is an enclosed basin with no connection to the ocean. The main challenges are Caspian water level fluctuations (which can rise or fall by meters over decades) rather than storm surges from the open sea.
The Netherlands: A Country Built Below the Sea
About 26% of the Netherlands lies below sea level, including most of its largest cities. Amsterdam sits at −2 m, Rotterdam at −1 m, and The Hague at just 0–2 m. The Dutch have been reclaiming and managing this land for over 1,000 years through an elaborate system of:
- Dikes: Over 3,500 km of primary flood defenses ring the country's vulnerable zones.
- Pumping stations: Windmills were the original pumps; today electric stations constantly remove water from "polders" (reclaimed land areas).
- Storm surge barriers: The Maeslantkering near Rotterdam — one of the largest moving structures on Earth — closes automatically when storm surge threatens.
- Delta Works: A network of dams, sluices, locks, dikes and storm surge barriers completed in 1997, called one of the Seven Wonders of the Modern World by the American Society of Civil Engineers.
New Orleans: A City in a Bowl
New Orleans sits in a natural bowl between the Mississippi River and Lake Pontchartrain, with most of the city at −1.8 meters (−6 ft) below sea level. When Hurricane Katrina struck in August 2005, the levee system failed catastrophically: 80% of the city flooded, water sat for weeks, and over 1,800 people died — one of the deadliest natural disasters in US history.
New Orleans' situation is worsening due to two compounding problems: sea level rise (the Gulf of Mexico is rising about 9 mm per year locally — faster than the global average) and land subsidence (the city is sinking 1–2 cm per year as sediments compact and groundwater is extracted). Projections suggest large parts of New Orleans could be 1–2 m further below sea level by 2100.
Jakarta: The Fastest-Sinking Major City
Jakarta, Indonesia's capital (which is being relocated to a new city, Nusantara), is sinking at an alarming rate — some northern parts are subsiding by as much as 25 cm per year. The cause is massive groundwater extraction: Jakarta's 10 million residents rely heavily on wells because the piped water system is inadequate. As groundwater is removed, the ground compacts. Combined with sea level rise, 40% of Jakarta is now below sea level. Annual flooding affects millions of residents.
How Cities Below Sea Level Protect Themselves
- Dikes and levees: Earthen or concrete barriers along coastlines and rivers hold back water. The Netherlands has over 3,500 km; New Orleans has 560 km of levees.
- Storm surge barriers: Massive moveable gates that close during storm surges. Examples: Thames Barrier (London), Maeslantkering (Rotterdam), MOSE (Venice).
- Pumping stations: Continuously remove groundwater and rainwater from protected areas. New Orleans has 120+ pumping stations — the largest urban drainage system in the world.
- Land use planning: Designating high-risk areas for parks, water storage, or low-density uses rather than housing.
- Floating and amphibious architecture: Some Dutch architects are designing buildings that float during floods or can withstand temporary inundation.
Climate Change and the Future of Low-Lying Cities
Rising sea levels — projected at 0.5–1.0 m by 2100 under medium emissions scenarios — will dramatically increase flood risks for low-lying cities. The IPCC estimates that without additional protection, annual flood damages in coastal cities could increase 100-fold by 2100. Cities like Jakarta, Miami, Bangkok, Ho Chi Minh City, and Alexandria are considered especially vulnerable. The Netherlands, despite its success, is investing billions in "Delta Programme" upgrades to maintain protection through 2100.
Frequently Asked Questions
Which city is most below sea level?
Baku, Azerbaijan at −28 m is the lowest capital city. The lowest permanently inhabited area is around the Dead Sea (Jordan/Palestine/Israel) at about −430 m. The lowest point on Earth is the Challenger Deep in the Mariana Trench at −10,935 m.
Is Amsterdam below sea level?
Yes. Amsterdam's city center sits at about −2 meters (−7 ft) below sea level. About 26% of the entire Netherlands lies below sea level, protected by a world-leading system of dikes, pumping stations, and storm surge barriers.
Is New Orleans below sea level?
Yes. Most of New Orleans averages −1.8 m (−6 ft) below sea level. Parts of the city are as low as −3 m. This is why Hurricane Katrina's levee failures in 2005 caused such catastrophic flooding — water could not drain out naturally.
How do cities below sea level protect against flooding?
Through dikes, levees, storm surge barriers, pumping stations, and urban planning. The Netherlands has the world's most advanced system. New Orleans, Tokyo, and Venice also have elaborate flood management infrastructure.
Will cities below sea level flood due to climate change?
Climate change poses a serious threat. Rising sea levels (0.5–1.0 m projected by 2100) combined with more intense storms will test existing flood defenses. Jakarta is particularly vulnerable and is already partially relocating its capital. Amsterdam and Rotterdam are investing heavily in upgraded defenses.