What was significant about the second battle of Ypres?

Related questions

1. Does everyone in Belgium speak French?
2. Is Bruges in Belgium or France?
3. Why did the battle of Passchendaele fail?
4. What happened at Ypres?
5. Was the second battle of Ypres a success?
6. How do you pronounce Ypres in Belgium?
7. How many died in Ypres?
8. Why did the Germans want Ypres?
9. How many people died at Flanders Field?
10. Who won Passchendaele?

Tags

1. #strategic
2. #during
3. #ypres
4. #battle
5. #western
6. #world
7. #fought
8. #april
9. #control
10. #germany
11. #poison
12. #flemish
13. #second
14. #belgium
15. #front
16. #first