Big pathfinding problem

[Reignking]

My construction workers are having trouble getting to a construction site.  The map is large, but with high water coverage.  I constructed a nice tourist area on the other side of the "river" (the northeast side of the lower island).  The river flows from the east side of the ocean, and ends on the west side of the island, where the isthmus is for people to walk.  

Anyway, the construction workers try to go to the southeast corner of the upper part of the land, across from the hotels, trying to cross, but cannot, when they should be using the isthmus to cross, like everyone else has.  

I have the saved game that I can upload, which would obviously explain this better.

[caddet]

That sounds familiar.  I have noticed that everybody seems to start out on a straight line from where they are to their destination, regardless of interference.  When they come to an obstacle such as a building, or a steep hill, or a bay or inlet, they will go around it.  The path around would seem to be the most direct route to their destination if there were no other obstacles for the rest of their trip.  If there are other obstacles, that means that the path they take may not be the best route.  And for some reason, they don't seem to "remember" anything about the route for the next trip, just the destination.  This seems to occur even when the obstacle is a building they have been to before.

[Coconut Kid]

...  The river flows from the east side of the ocean, and ends on the west side of the island, where the isthmus is for people to walk.  ...

It is highly doubtful that such an island resulted from the standard map generation routine. That routine produces fairly standard "round" islands with little in the way of projections or indentations no matter the size.

Therefore, one has to assume that the "river" described is the result of editorial terraforming by Reignking.

When one uses the editor to terraform the island and introduces such things as rivers, bays and peninsulas -- one has to live with a really screwed-up pathfinding system. Caddet is almost correct, but he is talking about trips of way more than 100 tiles - and he overemphasises buildings. There is a rudimentary memory for trips of around 100 tiles or less; and roads do help dodging buildings.