The communication trench ran from the rear areas up to the front line on the Bellewaarde Ridge east of Ypres. Soldiers walking it carried rations, ammunition, mail, and themselves up to the firing trenches and back. The Great Wall of China was unusually long and unusually high, built out of sandbagged parapets to protect against German observation. It needed a name and the soldiers gave it one. A small French cemetery had been established near the foot of the trench in 1914. When the 2nd Scottish Rifles took over the sector in June 1917, they adopted the existing graves and added their own, and called the place Perth - after the home town of their regimental predecessors, the 90th Perthshire Light Infantry. The cemetery sat just behind the front line throughout the Third Battle of Ypres. It was in use, taking new burials, until October 1917.

Captain William Henry Johnston was 35 years old in September 1914, an officer of the Royal Engineers, when his unit reached the Aisne river at Missy, France. The bridges had been destroyed. Johnston, under heavy German fire from the high ground on the far bank, operated two rafts for the entire daylight hours of 14 September - shuttling wounded men back to safety, ferrying ammunition forward to the men holding the bank. He was awarded the Victoria Cross. He survived a few months more. He was killed by a sniper on 8 June 1915, near Ypres, when he stood up to direct work on a trench. He was buried here, in Perth Cemetery, in the bigger grave of the war he had helped fight. He is one of two Victoria Crosses in this ground.

The other Victoria Cross belongs to Second Lieutenant Frederick Birks of the 6th Battalion, Australian Imperial Force. He had been born in Buckley, Flintshire, in north Wales, in 1894, the son of a coal miner. He emigrated to Australia in 1913 and enlisted in 1914. By September 1917 he had been at war for three years and had risen from private to second lieutenant in the field. On 20 September 1917, near Glencorse Wood during the Battle of Menin Road Ridge, Birks single-handedly captured a German strong-point after his corporal was wounded, killing the defenders and seizing a machine gun. Then he led a small party against another German position held by 25 men, killing ten and capturing the rest. The next morning, 21 September, he was killed by a shell while trying to dig out men buried in a dugout collapse. He was 23. The Victoria Cross was posthumous. His brothers in arms carried him back to Perth Cemetery.

Seven men buried at Perth were executed by their own army during the Great War, all in 1915, all for desertion. Their graves carry the same Portland stone headstones as the men killed by German fire - because the Commonwealth War Graves Commission, then as now, makes no distinction between the dead. On 7 November 2006, the British government issued posthumous pardons to all 306 servicemen executed during the war. Private George Ernest Roe, of the King's Own Yorkshire Light Infantry, from Sheffield, was the first of the seven; he was shot in June 1915. The others followed across that summer. What is in the official records is a date and a charge. What is not in the records, mostly, is whether the man broke under shell-shock, or fled from terror, or simply walked away because he could not bear another hour of the front. The 2006 pardon could not give them back. It could only say, eighty-eight years later, that what had been done to them had been wrong.

King Albert I of Belgium granted this land - and all the Commonwealth war cemeteries scattered across his country - to the United Kingdom in perpetuity, as a gift in recognition of the sacrifices made by the British Empire in the defence and liberation of Belgium during the war. The phrase 'in perpetuity' carried weight then and carries it still. The CWGC maintains the cemeteries permanently, mows the grass weekly through the growing season, replaces the headstones as they weather, plants the flowers chosen by Gertrude Jekyll a century ago. The grounds at Perth (China Wall) were designed by Sir Edwin Lutyens, who also designed the Cenotaph in London and the Stone of Remembrance that stands in every CWGC cemetery above 1,000 graves. The boundary wall, the entry pavilion, the geometry of the rows - all of it Lutyens. He worked across Flanders and the Somme for the rest of his life, designing rest for the men he had never met.