Hell on Earth, indeed
Here is an article in the (U.K.) Daily Mail with some hand-tinted photographs from the Third Battle of Ypres during World War I:
As the article points out, over 2000 soldiers died every day during this battle, which lasted for several months (July-November 1917). The ground was so torn up by artillery and flooded from rains that soldiers actually drowned on the battlefield.
Tolkien acknowledged that his own WWI experiences in this horrific setting inspired the “Dead Marshes” in The Lord of the Rings, but the reality here is more awful than anything Tolkien described.
Hat tip to Blue Crab Boulevard. ..bruce..