The arrival of the first four Mars inhabitants is just the beginning of this great adventure. The astronauts will be followed by more groups, spaced every two years, which will eventually lead to the base becoming a small village.
At first, expansion will be limited due to provisions, oxygen and water. Other landings will provide everything they might need to expand the colony: solar panels, new living quarters and plastic components. The settlement will develop as those inhabiting it become architects of their own environment.