SHIJIAZHUANG, May 26 -- At 91, the old man struggles to remember recent events but his memories of World War II are so fresh that he was able to draw a detailed battle map of his battalion's wartime missions.

Not only is Zhang Hengtai struggling with the onset of dementia, he never finished primary school and so is technically illiterate.

"To write the introduction, I had to search for each Chinese character in a dictionary that I borrowed from my granddaughter." The dictionary is now worn out, the pages dogeared and the cover battered.

It took the amateur cartographer six months to draw the map, which is about the size of two broadsheet newspaper pages, he used green for terrain details, black to identify roads and red to record his company's route.

He also marked out each of the seven battles they fought, and wrote down the names of his fellow soldiers.

Zhang is from an impoverished family in Boliugu Village in Handan in the northern province of Hebei. His father worked in a coal mine run by the Japanese, and was killed by a soldier in 1943 when Zhang was 19. Zhang joined the army later that year.

"I served in the Eighth Route Army led by the Communist Party," he said. "From 1943 to 1945, we travelled from Hebei to Shanxi, Henan and Shandong. A combined distance of about 4,000 kilometers." This is almost half the distance from Beijing to London.

Sometimes they walked for 50 kilometers a day, surviving on two meager meals of millet porridge a day.

"We mostly fought the puppet troops," he said referring to Chinese defecters. "We only met the Japanese army twice."

He recalled one battle in the spring of 1945, when his company was lying in wait to ambush the enemy.

"We were hiding by the roadside when eight trucks carrying the Japanese arrived." It became quickly clear that their equipment was dwarfed by that of their enemy.

"The Japanese had heavy machine guns and sniper rifles," he said, adding that his troop were only armed with rifles. Japanese snipers killed everyone in the vanguard platoon.

Zhang's regiment was defending the command center and had not been ordered to directly attack but of the 150 soldiers, only 30 escaped without injury. Zhang was shot in the leg. It still hurts sometimes.

On August 15, 1945, the Japanese surrendered. To celebrate, Zhang ate his first substantial meal for years.

This year is the 70th anniversary of the end of the WWII. Zhang said he drew the map as a way to commemorate the years he spent fighting.

"During those years our nation showed its perseverance despite all setbacks," he said. "I want the younger generation to understand our history, so that they will never forget those who died for the peace and prosperity that they enjoy now."