Who would cleanup battlefields after everything was said and done? What was the last reported finding of intact battlefields? Were there burnt out vehicles and bodies still being found decades later? I imagine jungles in the Pacific Islands being littered with bodies and vehicles. Do these still exist?
I would recommend Aftermath: The Remnants of War by Donovan Webster, as he visits and writes in depth regarding the leftovers of Stalingrad in the early 1980s. He describes walking through snow fields with bones as far as the eye can see, as well as rows of bunkers and piles of abandoned equipment. From the way Webster describes it, the only leftovers of the battle that were actually removed were the larger vehicles, such as tanks and halftracks. His guide follows a map he found in a German camp that outlined the locations of the various German division encampments, that to his guide described as " There is no civilization where we're going, it is only earth and snow. Big. Empty and very difficult during the winter".
Besides the portion on Stalingrad and the surrounding battlefield remnants, he covers the aftermath of Vietnam, Desert Storm, and the ongoing cleanup of French battlefields from WWI. However, I found his writing on the Stalingrad portion the most interesting and somewhat distubring, as I found it hard to believe everything was simply left out there for decades.
Edit Reason: Further context.