0.19.1996 Caravan cannot leave the area despite having a "reachable side"

[erdrik]

The map Im on is covered by mountains on the east edge, and the coast to the ocean on the west side.
The south side has an open edge, but a path to my colony is blocked completely by mountain and walls about 60 tiles from the edge.
The north side is completely open, and there is a free and open path from my colony to that edge.

Whenever I try to form a caravan it claims that the caravan cannot leave and that I need to make sure I have at least one side reachable.

EDIT:
Even after making a hole on the south side, it still tells me I need to have "at least one side reachable", despite there now being two sides reachable. I officially cannot create caravans.

[erdrik]

The save file.


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[Ramsis]

Thank you erdrik.

[Kenneth]

In your savegame's colony map you have clear passage at the top and bottom, but those world tiles are impassable (see attachment "overview", 1 and 2 are impassable, but 3 is passable).
If you excavate a tunnel towards a passable world tile, the caravans will be able to leave your colony (see attachment "tunnel").

To avoid confusion we increased the range of map edges, so you can now reach up to 3 neighbouring world tiles from one map edge. Thanks for reporting

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