The Caravan is a building that allows players to recruit creatures from external dwellings or towns, and then have them transported to the town without needing to travel with heroes. The number of turns before it appears at the town depends on the distance it has to travel. It first appeared in Heroes of Might and Magic IV, and while it doesn't appear in regular Heroes of Might and Magic V, the concept returns in the expansions.
Heroes IV[]
Haven caravan building in Heroes IV
In Heroes IV, the caravan is a building that can be built by all factions, and costs 4000 gold and 10 wood. The player can hire creatures from dwellings and have them transported to the town, or send creatures between towns. Both towns must have a caravan, and the creatures must be hired before they can be placed in the caravan.
There must be a clear path between the dwelling and the town, or between the towns, before a caravan can be sent. Enemy or neutral creatures that stand in the way will make it impossible to send a caravan, but once it's underway, the caravan can't be stopped.
If the town is captured by enemies before the caravan arrives, the creatures will appear outside the town instead. If the caravan included a hero, the player may use that hero to attempt to retake the town.
Heroes V[]
Heroes V caravan on the adventure map
In Hammers of Fate and Tribes of the East, sending caravans doesn't require a building to be built. The player can simply hire creatures from other towns or from external dwellings, and they will be transported to the town. But unlike in Heroes IV, creatures that have already been purchased can't be placed in a caravan.
In addition, caravans won't be transported invisibly towards the town between turns, but will instead travel on the adventure map, where the enemy can track their progress, and even attack them. If neutral or enemy creatures get in their way, the caravans will stop, unable to move until the path has been cleared. Since caravans can't attack, only defend themselves if attacked, enemy players may choose to place a weak hero in front of a strong caravan, locking it in place while the rest of that player's forces are dealt with.
Heroes VII[]
The feature returns in Might & Magic: Heroes VII.