On the outskirts of Strasbourg near the French-German border lies a cemetery where the bodies of more than 6,000 French and German soldiers are interred. Alsace has been a contested site throughout history, its ownership passed between the two great powers of continental Europe.
In recent years, the city of Strasbourg has evolved as a symbol of a united Europe. The city's magnificent Gothic cathedral which soars into the sky and dominates the landscape for miles competes for attention with the sparkling modernity of the glass-facaded European Parliament, a powerful visual juxtaposition of old and new Europe.
Today, that vision of a hopeful, forward-looking Europe underpinned by the European Union lies in ruins. Britain's vote to leave the EU on June 23rd represents the greatest challenge to the European project since its inception.
Like Banquo’s ghost, Britain was a deathly presence at Wednesday’s meeting of EU leaders in Brussels, its empty chair a stark reminder that the union of 28 members was soon to become 27.
The principle of ever-closer union and expansion that has propelled the bloc has been turned on its head as a country has voted to leave.
A line has been crossed, a taboo broken, as the possibility of the gradual disintegration of the European Union has edged into view.
How did it come to this?
Speaking this week in Bratislava as he launched Slovakia's presidency of the EU, its prime minister Robert Fico said leaders had failed to communicate the benefits of the European Union to its citizens. Standing near the river Danube, just kilometres from the historic border where east met west during the Soviet era, he recalled how difficult it had been to travel to Vienna, located just 60 kilometres away, before 1989.
“When the border opened it was a very emotional moment . . . If you ask a 20-year-old their view on Schengen nowadays, they take it absolutely for granted. They see no contribution by the European Union, the role it played in this benefit,” Fico said.
The EU's generation gap is increasingly a problem. Martin Schulz and Jean-Claude Juncker, the heads of the European Parliament and European Commission respectively, are unapologetically pro-EU federalists: they are both in their 60s and grew up in the shadow of the second World War, and the ravaged Europe of their parents' generation haunts them.
As time passes, that message is losing relevance. While some believe Europe’s problems began when it changed from being a project of peace to an economic and monetary union,the truth is that economics always underpinned the foundations of the EU.
A primary motivation was, of course, preventing German domination after the war by creating a 20th century version of the concept of Europe that governed international relations in 19th century Europe by ensuring the balance of power through a system of alliance. But it also had economic motivations. The creation of the European Coal and Steel Community in 1951 was a recognition that Europe needed to pool its economic resources if it were not to be crushed economically by the rising superpower to the west across the Atlantic and the Soviet one to the east.
However, while the idea of Europe continued to thrive, bolstered by the reunification of Germany after 1989, the notion of the European Union as a political expression of a European identity was running into difficulty.
As the structure and mechanics of the European Union became more and more complex as it integrated further, the institution moved further away from its citizens.
Ironically, it was the EU’s own drive for consensus and accountability that created a labyrinthine system – as EU legislation was increasingly forced to go to the different institutions for approval, the legislative process took years.
Similarly, the EU’s great achievement – its ability to get 28 very different member states to agree to common proposals – has resulted in a system obsessed with consensus and compromise, with the result that many of its solutions are half-baked compromises. It means that when events such as the euro zone and refugee crises strike, its tools are insufficient, and instead it falls to its economically strongest member, Germany, to take a reluctant leadership role.
The central paradox facing the European Union in the 21st century is that, in order for projects such as the single currency to work, there is a need for more integration and centralisation of resources, such as a single euro zone finance minister and budget. But citizens do not want further integration.
The EU is caught in an endless no man’s land between the need for further integration and the desire by citizens to retain as much national sovereignty as possible.
As the European Union comes to term with the UK referendum result, it is not clear what direction the project will take.
The firm message from Brussels in the wake of the vote is that there will be no immediate change in policy and no move towards federalisation.
Even the most ardent supporters of EU integration recognise that this is not the time to talk of greater integration, when so many countries, as well as Britain, are grappling with Euroscepticism.
A meeting of EU leaders on September 16th in Bratislava will offer the first major moment of reflection for the EU, with a further gathering expected in Rome next March to mark the 60th anniversary of the Treaty of Rome.
Ironically, while the decision by the UK to withdraw from the European Union had expected to revitalise Eurosceptic movements in other countries, the referendum result may have the opposite effect.
The shock of the result and the economic and political turmoil that have engulfed the UK may instead consolidate support for the European Union in other countries, as indicated in this week's general election in Spain where the main centre-right party performed better than expected.
For the optimist, the British exit may in fact be the wake-up call needed for the EU and its citizens to appreciate what they have and work to make it better.
What is certain is that, whatever the fallout from the British referendum result, the European Union will continue to survive, in whatever form, with or without Britain.