D&D General Red Wavy Lines

[tconnolly88]

There is a D&D adventure map with red wavy lines. Can anybody tell me the meaning? Am I allowed to post a very-close up picture here? Thanks.

 

[Distracted DM]

There is a D&D adventure map with red wavy lines. Can anybody tell me the meaning? Am I allowed to post a very-close up picture here? Thanks.

Post a pic so we have some idea, yes go for it.