In the second episode of Traces of War - James continues his journey across Europe. This time he will be visiting the site of some of the biggest military engineering projects undertaken during the Second World War.

His journey starts in Belgium where James explores the enormous super fortress Eben Emael. Built during the 1930s, it was supposed to deter any future invasions of Belgium from the East. James will find investigate some of the massive remaining casemates that were packed with massive cannons and the latest in fortress technology. James will also find out about what happened when a group of just 78 German airborne troops landed on the fort in the first hours of Hitler's invasion of the West.

For his second stop he is heading back to Normandy, to the town of Arromanches, to explore the remains of the enormous Mulberry Harbour. He will find out about why the Allies decided to bring a port with them across the channel - and exactly how it was made.

In the final stop of the episode he heads to the last year of the war - and to the Western German border. Here, hidden away in forests and next to villages are the remains of the Siegfried Line. The line - a string of defences built by the Germans from 1936 - were designed to deter any Western powers from attempting an attack on Germany. Originally the line stretched from the border with Switzerland in the South to the border with the Netherlands - but some of the best preserved sections can be found in the Hurtgen Forest. James will find out about the building of the line and why it was important - but will also discover the grim reality for the men from the US army who had to come face to face with it in the Hurtgen Forest in September 1944.