Detail from the Monument to the Martyrs of the Two World Wars, Charleroi / Alamy

Harriet O’Brien pays tribute to the towns that bore the first onslaught

As Belgium prepares for next year's centenary of the outbreak of the Great War, there's a growing sense of poignancy and reflection. There is, of course, much to contemplate across the country, but perhaps especially so in the French-speaking south: it was in Wallonia that the first battles of Europe's four-year conflict were fought.

On 3 August 1914 Germany and France declared war on each other – and the Kaiser demanded permission for his troops to cross Belgium to attack the French. Under the Treaty of London of 1839, Belgium was recognised as a neutral country. Albert I, King of the Belgians, refused the Germans, famously commenting that "Belgium is a nation, not a road". The following day, in flagrant breach of the treaty, the Kaiser's army marched across the border, expecting their tiny neighbour to put up no resistance.

But the German commanders had reckoned without the Belgian army, which managed to hold off the Kaiser's advance – winning time for the French to mobilise their forces. Meanwhile, the British marshalled their troops and came to Belgium's aid. And so it was that they too were drawn into war on the Western Front. Britain would now have to fight Germany, her ally against Napoleon in Waterloo a century earlier.

South of Brussels are five heroes of the invasion and subsequent occupation – five towns that suffered very different wartime experiences. Close to the German border, rich and industrial-yet-leafy Liège was the first objective of the invasion force. It was protected by a ring of forts whose vastly outnumbered and outgunned soldiers valiantly withstood the enemy troops for 12 days, forcing them to use their secret weapon – the huge "Big Bertha" howitzer – ahead of schedule. But one after the other these defensive outposts were taken, and on 16 August the last troops withdrew.

Nearby Namur, for centuries a much fought-over strategic point on the confluence of the rivers Meuse and Sambre, was laid under siege. It fell to the Germans on 24 August. Namur was also ringed by defensive forts, and there the Belgian army came under an avalanche of fire while terrified civilians fled from the area (12,000 survivors reached Rouen and beyond).

Further west, Charleroi – the powerhouse of Belgium thanks to its hugely productive coal mines – was the arena of a particularly brutal confrontation between the French and the Germans. After three days of intense fighting the French troops retreated on 23 August.

Moving west again, it was around the pretty city of Mons that British troops entered the fray. The Battle of Mons raged on 23 August. The Germans gained possession of the town, and the British were forced to withdraw. So, militarily, it was a defeat for Britain. However, in terms of morale, and in delaying the German advance to the Marne, the British were to claim a psychological victory, not least with the birth of the legend of the Angels of Mons.

Near the border with France, the ancient town of Tournai fell to the Germans in late August. It was here, as the war entered its final days during November 1918, that part of the Battle of the Escaut River was fought.

These five towns today are spirited survivors, and catching this atmosphere is part of the pleasure of a visit. Variously presenting an array of striking architecture and great food, they are all places in which you will want to wander around and browse their many attractions.

Some offer substantial First World War sites; others are worth exploring for their remarkable museums, which bear testimony to the courageous character of the people from the areas and to a strong heritage of revival and reinvention. For example, Charleroi, once enormously wealthy, floundered when its industry slumped in the 1970s and 80s, becoming a shadow of its former self. Yet thanks to a major renovation – and a busy, no-frills airport – it is bustling once again. Then there's Tournai, which was all but destroyed by bombing during the Second World War but has been painstakingly resurrected. The last property to be rebuilt in its magnificent Grand Place was completed just six years ago.

All five towns are easy to reach from the UK, and in the build-up to next year's First World War tributes a trip to all or any of them is more rewarding than ever.

Getting there and getting around

Access from the UK is quick and easy by train or plane. Brussels Midi station is two hours from London St Pancras on Eurostar (08432 186 186;, or less from Ebbsfleet or Ashford.

With an “Any Belgian Station” Eurostar ticket you can travel by train anywhere in the country at no extra cost so long as you complete your journey within 24 hours of arriving in Brussels (not valid, however, on Thalys or ICE trains).

Swift onward rail connections take you to Liège, Namur, Charleroi, Mons and Tournai and rail services run regularly between the five towns. See for details.

Brussels National airport, 14km from the centre of the capital, is served by Brussels Airlines (0870 600 1728; from Bristol, Edinburgh, Heathrow and Manchester; by British Airways (0844 493 0787; from Heathrow; and by BMI Regional (0844 4172 600; from East Midlands.

Brussels South Charlero airport, about 8km from the centre of Charleroi, is served by Ryanair (0871 246 000; from Edinburgh and Manchester.

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