This, once in a while a land swap if needed. Else no one cares. The Dutch are fun neighbours.
To mark the centennial of Finnish independence, there was a campaign in Norway to give the Finns a few hundred square metres of Norway, so that they could get a highest point which was indeed a local maximum.
Too bad the Norwegian constitution says you cannot give away bits of the country; a land swap was suggested to ensure both countries remained the same size afterwards, but apparently this, too, would violate the constitution...
(Not as hard as it may sound; the border isn’t marked as such, only with the occasional pole here and there.)
Considering all the notes being passed back and forth afterwards, the conscripts must be kicking themselves for not keeping quiet about it; they weren’t observed by Finnish border guards; rather, they notified their officers when returning to base that they’d crossed the border; the army notified the DoD, which notified the Foreign Department, which notified the Finns, who said ‘Huh?’