A mayor’s proposal to build a bridge from the mainland to the Curonian spit – a long curved sand dune spit on Lithuania’s Baltic coast – has reignited a familiar European debate. How can you balance UNESCO heritage preservation – in this case the Curonian spit – with modern development needs? While one side argues the bridge would reduce ferry pollution, UNESCO Commission Chair Agnė Jasinavičiūtė warns it could cost the site its World Heritage status, considered “an outstanding example of a landscape of sand dunes that is under constant threat from natural forces”. It was a bridge construction that cost Germany's Dresden Elbe Valley its heritage status in 2009.

The controversy mirrors challenges across the world, such as in Vienna, where they face heritage warnings over high-rise projects in the centre of the capital, and in the Everglades national park in Florida, where the mangrove ecosystem is threatened by nearby urban growth.