Areas on the map that you can go to but can't unfog

Does anyone know how come there are some areas on the Tyria world map that you can go to but it will not unfog on the map? Thanks.

I wasn't aware of any. Can you name them?

Well, like the area southwest of Sardelac Sanitarium in Old Ascalon. You can walk there, but the map will still be foggy.

There are some, can't name them, but it doesn't cause any troubles concerning the Carto-title.

So..../bug?

Do they count toward Carto title?

the west side of Sardelac you can't go, where the catacombs were in pre. Once outside Sardelac, you can go south, east and north, but you can't go west unless you go north for a bit and around.

Those area count for cartography : it's not because the fog won't disappear that it won't give you +0.01 (stupid Tyria that takes forever to map xD).

Yes, that's what I meant, go north for a bit and around, you end up at southwest. Across the bridge is where the map won't unfog.