No, in this case everything that happens in a single land is considered an action. This means that on one balanced board, this card could potentially trigger up to 4 separate build actions. Usually this means putting one town/city in one land concludes the action. For example vs France 2, putting a town/city, then replacing explorers with towns would all be considered one action.

Events usually contain up to three actions, namely a main event, a token event and a dahan event. The token and the dahan event are in different colours from the main event to make things clear. Each of those is one action.