Baku, Azerbaijan, is the world's lowest-lying capital city at roughly 28 metres below sea level, on the shore of the Caspian Sea. Other major urban areas partly or wholly below the waterline include Amsterdam and Rotterdam in the Netherlands, New Orleans in the United States, Jericho in the West Bank, and the Jordan Valley towns near the Dead Sea — each of which sits low for a completely different reason.
Baku sits lower than any other capital
Baku's elevation of about 28 metres below sea level has nothing to do with flood defences. It is a consequence of the Caspian Sea itself being an endorheic basin — a body of water with no outlet to any ocean. Its surface level is set purely by the balance between river inflow, chiefly the Volga, and evaporation, and that surface currently sits well below global sea level.
Because the reference point is a shrinking inland sea rather than the ocean, Baku faces the opposite problem from most low-lying cities. The Caspian's level has fluctuated substantially within living memory, rising roughly two and a half metres between the late 1970s and the mid-1990s and flooding coastal infrastructure, then falling again since. Recent measurements show continued decline, and projections for the coming century are severe enough that the concern in Baku is a retreating shoreline and stranded port facilities rather than inundation.
The city is genuinely dry land in no danger from the Atlantic or Pacific. The Caspian Sea's geography makes it a closed system, and Baku's statistic is a quirk of how sea level is defined globally.
The Dutch answer: make the land, then defend it
The Netherlands is the only country to have organised its entire national existence around this problem. Roughly a quarter of its land area lies below sea level, and something over half is vulnerable to flooding from sea or river. The lowest point, near Nieuwerkerk aan den IJssel, is about 6.7 metres below sea level.
Much of that land was never naturally dry. Polders are created by enclosing an area with a dike and pumping the water out — historically with windmills, since the fifteenth century, and now with electric stations. Once drained, peat soils compact and oxidise, so the ground surface sinks further, requiring more pumping. The system cannot be switched off; drainage is a permanent operating cost, not a one-off construction project.
Two catastrophes drove the modern defences. The 1916 Zuiderzee flood led to the Afsluitdijk, a 32-kilometre barrier completed in 1932 that converted a saltwater inlet into the freshwater IJsselmeer and enabled the reclamation of Flevoland. The North Sea flood of 1953 killed over 1,800 people in the Netherlands and prompted the Delta Works, a system of dams, sluices and storm surge barriers finished across the following decades. Dutch flood defences are engineered to probabilistic standards — some densely populated areas are protected against events estimated at once in ten thousand years.
Amsterdam itself sits around 2 metres below sea level in parts, and its buildings stand on timber and concrete piles driven through soft peat and clay into firmer sand beneath. The canal network is drainage infrastructure that happens to be beautiful.
New Orleans and the bowl problem
New Orleans presents the same geometry with a far worse risk profile. Roughly half the city lies below sea level, reaching about 2 metres down in parts of Lakeview and the Lower Ninth Ward, with the highest ground along the natural levees of the Mississippi.
The city's founders built on that high ground in 1718 precisely because it was the only dry land. Expansion required draining the backswamp behind it, which began in earnest in the early twentieth century. Draining organic soil caused it to compact, and large parts of the city that were at or slightly above sea level in 1900 have since subsided several metres. The subsidence was caused by the drainage itself.
The critical difference from the Netherlands is what surrounds the bowl. Levees along the Mississippi and Lake Pontchartrain hold water that sits higher than the neighbourhoods behind them, so a breach fills the low ground and it cannot drain out by gravity. Hurricane Katrina in 2005 demonstrated this: the majority of flooding came from levee and floodwall failures rather than from water overtopping the defences, and the water had to be pumped out over weeks. Confining the Mississippi between levees also prevents the sediment deposition that once built and maintained the delta, so the wetlands that formerly buffered storm surge continue to disappear. Our guide to New Orleans geography traces how that delta was formed.
The Jordan Valley and the world's lowest settlements
The Dead Sea shore is the lowest exposed land on Earth, currently around 430 metres below sea level and falling. Jericho, at roughly 258 metres below sea level, is the lowest permanently inhabited town anywhere, and has strong claims to being among the oldest continuously occupied settlements in the world.
The cause is tectonic. The Jordan Rift Valley is part of the boundary between the African and Arabian plates, where the crust is being pulled apart and the floor of the valley has dropped. Like the Caspian, it is endorheic — the Jordan River flows in and nothing flows out.
The Dead Sea is currently retreating by roughly a metre a year, because most of the Jordan's flow is now diverted for agriculture and drinking water before reaching it. The retreat has exposed former lakebed where dissolved salt layers are being flushed by fresh groundwater, producing thousands of sinkholes that have swallowed roads and buildings along both shores. The Dead Sea's geography is changing faster than almost any other major landform.
The lowest points on each continent
Setting cities aside, the continental low points give a sense of how unevenly these depressions are distributed — and how few of them are habitable at all.
- Asia — the Dead Sea shore, about 430 m below sea level, the lowest exposed land on Earth
- Africa — Lake Assal in Djibouti, roughly 155 m below sea level, a hypersaline crater lake in the Afar Depression
- North America — Badwater Basin in Death Valley, about 86 m below sea level and among the hottest places recorded anywhere
- South America — Laguna del Carbón in Argentina's Santa Cruz Province, roughly 105 m below sea level
- Europe — the Caspian Depression, around 28 m below sea level along the Russian and Kazakh shore
- Australia — Lake Eyre, about 15 m below sea level, usually a dry salt pan
- Antarctica — the Bentley Subglacial Trench, some 2,500 m below sea level, though buried under ice rather than exposed
The pattern is consistent: almost every one is either a rift valley floor or an endorheic basin where evaporation exceeds inflow. Both are arid by definition, which is precisely why so few of them support cities. Death Valley has no urban settlement for the same reason Lake Assal has none.
Two different kinds of risk, often confused
Being below sea level and being at risk of flooding are related but distinct, and conflating them produces bad intuitions.
Cities on endorheic basins — Baku, Jericho, the Turfan Depression in China at about 154 metres below sea level — are below the global datum but are not threatened by the ocean at all. There is no hydraulic connection. If anything, their water bodies are shrinking.
Cities behind defences — Amsterdam, Rotterdam, New Orleans — are below the level of water that is physically adjacent and held back by engineering. Their risk is entirely a function of that engineering.
And a third group is at severe risk while sitting above sea level. Jakarta is subsiding by up to 25 centimetres a year in its worst-affected northern districts, driven largely by groundwater extraction, and parts of it have already dropped below the waterline — which is why Indonesia has committed to relocating its capital. Venice, Bangkok, Ho Chi Minh City and Manila face comparable subsidence.
The comparison that matters is not elevation but the combination of three things: how far below the adjacent water a place sits, how fast the ground is sinking, and how much a society is willing and able to spend on defences. The Netherlands is far lower than Jakarta and far safer.
Where the next entries on this list will come from
Two processes will lengthen the list, and neither is speculative.
Subsidence is the faster of the two. Groundwater extraction compacts aquifers, and in rapidly growing cities without adequate piped supply the effect is dramatic — several times faster than any plausible rate of sea level rise. Restricting extraction can slow or halt it, as Tokyo demonstrated after severe subsidence in the mid-twentieth century, but compaction of clay layers is largely irreversible.
Sea level rise then shifts the reference point beneath every coastal city simultaneously. Global mean sea level has risen roughly 20 centimetres since 1900 and the rate has accelerated, with projections through 2100 varying with emissions but generally spanning several tens of centimetres to over a metre.
The responses being attempted differ sharply. Jakarta is relocating its capital functions to Nusantara on Borneo. Indonesia and Jakarta are also building a coastal sea wall. The Netherlands has moved toward "room for the river", deliberately giving floodwater space rather than confining it further. Venice's MOSE barriers, operational since 2020, close the lagoon during high tides. Each is a bet on a different answer to the same question, and the countries with land below sea level guide sets out the national picture behind these cities.