You are on an island in the middle of a lake.
The lake is in a remote part of the country and therefore there has never been a bridge connecting the island to the mainland.
Every day a truck gives rides around the island.
Puzzled as to how the truck had gotten onto the island, you ask around and find out that the truck was not transported to the island by boat or by air.
Nor was it built on the island.
Explain how the truck got there?