A shipment will be transported from the third countries via international border and borrow inland of other nation to transport cargo to the end point is called transit cargo (in-transit).
Some nations and special economic zones don’t have sea port and these nations must use sea port of other nations to import or export their cargo
Some example with nations as below :
Laos is a nation which don’t have any sea port, all cargo import from China must transit via inland of Vietnam through between Vietnam – China border and Vietnam – Laos.
Cambodia is a nation which have small sea port, don’t allow huge carrier mooring or some special economic zones (SEZ) place near the border as Moc Bai – Bavet border