If there is something truly distinctive about Greek cities, it’s the paradox of how they grow. Expansion almost always comes first — sometimes legally, by bending construction rules to their limits, and sometimes outright illegally — and only later does the state rush to catch up, reshaping its urban and spatial plans to fit what’s already been built.
Elsewhere in Europe? It’s a completely different story.
Rules and reason have long been absent from the country’s urban development, and the results are now impossible to ignore. Take Patras, for instance. This year’s major wildfire burned through its suburbs — a predictable consequence in a city that has “stretched” by 103.5% since 1985, mainly eastward, until buildings now stand right beside forested areas.
Across Greece, what used to be peri-urban zones have turned into dense cityscapes in just a few decades, all in the name of the right to “a roof over one’s head.”
The latest findings from a study by the National and Kapodistrian University of Athens (NKUA) paint a revealing picture. The research links the changing thermal environment of selected Greek cities with the surge in built-up surfaces between 1985 and 2022.
In Ioannina, the built-up area today is nearly twice what it was forty years ago — up by 188.5%. Cities such as Kalamata, Lamia, and Patras have more than doubled, while Larissa and Katerini have expanded by 77.2% and 66.4% respectively.
Even cities like Thessaloniki, Alexandroupoli, Volos, and Heraklion — where the increase is around or above 50% — remain far more overbuilt than their European counterparts. The result? An explosion of concrete that has made these cities increasingly vulnerable to high temperatures and the heatwaves driven by the climate crisis.
When Cities Overbuild, the Heat Follows
“The excessive construction seen in many Greek cities has led to dense, tall buildings, often crammed along narrow streets that restrict natural ventilation — and to a severe lack of open spaces,” explains Professor Konstantinos Kartalis, environmental physicist at NKUA and member of the EU Scientific Committee on Climate Change.
He adds that “the disappearance of parks and the replacement of natural surfaces with concrete and asphalt have created conditions that worsen the urban climate. Buildings absorb, store, and radiate heat into their surroundings, intensifying the ‘urban heat island effect’.”
According to Dr. Kostas Filippopoulos, a researcher at NKUA, every city examined through satellite data shows the same pattern: a steady rise in average annual temperature since 1985, along with growing temperature anomalies. “These anomalies,” he notes, “refer to higher summer air temperatures — especially since 2000 — compared with the 1980–2010 climate average.”
In August, such anomalies reached or exceeded 2°C, with the sharpest increases recorded in the past decade. “Coastal cities experience some relief from sea breezes,” Filippopoulos says, “but in places like Thessaloniki, Volos, and Patras, tall buildings along the waterfront have partly blocked that natural cooling effect.”
Essentially, he adds, the rising average and anomalous temperatures show the combined impact of urbanization and climate change — the latter unfolding faster in the Mediterranean than almost anywhere else on Earth.
In several cities — Thessaloniki, Patras, Larissa, and Volos among them — researchers identified moderate to strong urban heat islands, where air temperatures are consistently 1.5°C to 3°C higher in central districts than in the surrounding countryside. According to Professor Kartalis, “when temperatures stay high at night, as they do in cities, the human body experiences far greater heat stress.”
A German study analyzing the past 15 years found a notable rise in strokes linked to high nighttime temperatures.
The urban heat island, he explains, is the measure of a city’s thermal load — a product of concrete, asphalt, human activity, and trapped heat. And, as the NKUA study makes clear, Athens is far from alone in this.
Concrete’s March on Thessaloniki
Thessaloniki is no exception. Within the city, researchers have identified smaller “heat islands” — districts that record consistently higher air and surface temperatures than neighboring ones. The causes, they say, are threefold: the city’s size, its dense and tall buildings, and the lack of green or open spaces.
Across the wider metropolitan area — including Thessaloniki, Kordelio-Evosmos, Ampelokipoi-Menemeni, Neapoli-Sykies, Kalamaria, and Pylaia — the urban fabric has expanded by 54.8% in all directions. The sprawl is most visible to the west, worsening traffic, and to the southeast.
Local Patterns and “Starfish” Cities
In Patras, expansion to the east has pushed construction right up against forest land. Ioannina has seen its building boom extend mainly toward the university area. In Kalamata, the spread of concrete has more than doubled — though, interestingly, the city grew inland rather than along the coast.
Heraklion followed a similar pattern, expanding mostly southward.
Volos, on the other hand, has stretched eastward along the shores of the Pagasetic Gulf, spilling past the ring road and creeping up toward the lower slopes of Mount Pelion. Larissa and Katerini have grown radially in all directions, swallowing up nearby settlements — their map outlines now resembling starfish.
Data analysis by NKUA also shows that all these cities have grown taller. Single-family houses are being replaced by apartment blocks — a shift that not only changes their character but also worsens microclimatic conditions at street level.
The Wrong Recipe for Growth
“The development of regional cities in Greece over the past 35 years has been decisive in shaping both their urban fabric and their socio-economic dynamics,” says Professor Kartalis. “But with few exceptions, the recipe has been wrong.”
Excessive building, oversized volumes on narrow streets and coastal fronts, limited green space, and the absence of coherent urban planning have degraded local climates, he explains, leaving cities dangerously exposed to extreme heat — with serious implications for public health and quality of life.
“What’s striking,” he adds, “is that parts of the engineering and construction sector still push for larger building volumes. The NKUA study highlights the urgent need to connect urban development with environmental and climatic parameters — and to prioritize climate adaptation plans. Cities can no longer afford to ignore these consequences.”
“Without a fundamental rethink of how cities are designed and function,” he warns, “they risk becoming ever more vulnerable and less livable — undermining not only residents’ quality of life but also their ability to adapt to future challenges.”
The Building X-Ray
According to the 2021 building census published by the Hellenic Statistical Authority (ELSTAT), Greece has around 4.28 million buildings, of which 1.8 million — more than 40% — were constructed after 1985.
Most have reinforced concrete frames (60.6%), followed by brick and cement blocks (19.2%), stone (17%), and metal (1.3%).
Source: tovima.com
VIA: https://www.ot.gr
