If you're talking about WW2, it's the battle of Stalingrad.
If it's about WW1, it would probably be Verdun.
Sorry but i dont think a lot of people know this
Besides silk, the Chinese also exported (sold) teas, salt, sugar, porcelain, and spices. Most of what was traded was expensive luxury goods. This was because it was a long trip and merchants didn't have a lot of room for goods. They imported, or bought, goods like cotton, ivory, wool, gold, and silver.