Global warming could deprive Spain of cultural treasures including the Vizcaya Bridge near Bilbao, the Roman lighthouse near La Coruña known as the Tower of Hercules and Seville's stunning cathedral — the third largest church in the world.
Also on the Spanish hit list are Seville's Alcazar palace, its Indias Archive and the Roman archaeological site in Tarraco, Ibiza.
That's the conclusion of a new study looking at the potential loss of world heritage worldwide through global warming.
"When thinking about climate change, people usually think about ecological and economic consequences," Ben Marzeion, study author and climate scientist at the University of Innsbruck, told The Local.
"We wanted to add another dimension: what might the cultural impacts be? Culture is hard to quantify, but for the Unesco list there is general agreement that these sites are significant and worthy of special consideration and protection," he explained, adding that Unesco had not funded the study.
Using sea level rise estimates and topographic data, Marzeion and his team looked at the impact of rising sea levels in different countries over the next 2,000 years.
"In this time scale, ocean heat content and glacier ice mass can be considered to be in equilibrium with global temperatures, and relatively independent of the warming path of the initial 100 years," the Germany and Austria-based study authors said.
The scientists also found 40 Unesco sites worldwide would be affected by rising oceans over the next 2,000 years if global warming continued at the same rate.
But they found that a "not improbable" three-degree Celsius rise in temperature over the same period would have an even more serious impact, affecting 136 Unesco sites globally.
The researchers in the study published in the journal IOP science recognized the difficulty of making models of climate change, and also admitted they hadn't taken into account local conditions like flooding.
But they said the consequences of inaction could be disastrous.
"Our analysis illustrates that the spatial distribution of the existing and potential future cultural world heritage makes it vulnerable to sea-level rise," the study authors wrote.
"Future generations will face either loss of these sites, or considerable efforts to protect them," they warned.
While Marzeion conceded he was not a specialist on coastal protection, he did tell The Local that technical solutions including "the building or upgrading of dykes" might be possible for some sites.
However "for some sites it will be hard to do anything at all — particularly in those places where the site is directly on the shore line," he added.