樹海

1. Origins, structure, and basic meaning

• Structure: 樹海 (じゅかい) combines tree 樹 and sea 海 to portray a vast, dense forest as a sea of trees.
• Basic usage: It describes woodland spreading beneath a viewpoint or deep enough for travelers to become lost.

2. Common pitfalls and similar expressions

• A forest described through a sea metaphor
  • The 海 in 樹海 expresses breadth and density; it does not indicate an actual body of water.