What are City Expansions?

Expansion:Strictly speaking, your building site is also a resource in the city – you'll notice quickly that the available space is limited. But you do not need to constantly sell buildings – you can also increase the size of your city. To do this, you must unlock expansions. Investigate technologies for this purpose or conquer provinces on the continent map to give you the expansions. You can find them in your building menu – pay the costs and place them adjacent to your city. Additional expansions are available to you for Diamonds or medals. But expanding or tearing down is not your only option to accommodate more buildings in your city – compare buildings with regards to size and effects. Smaller, more efficient buildings will help to save space!

You can see below a table with all expansion type by age. There is 3 categories of expansion: those you can win in the tech tree and the campaign map, those you can buy with diamonds, and those you can buy with medals. Medals expansions are not related by ages.

Expansions by age

	Tech Tree	Campaign	Premium	Total per age
Bronze Age	4	1	2	7
Iron Age	5	2	2	9
Early Middle Age	4	2	2	8
High Middle Age	5	2	2	9
Late Middle Age	5	3	2	10
Colonial Age	3	2	2	7
Industrial Age	2	3	2	7
Progressive Era	2	2	2	6
Modern Era	2	2	2	6
Postmodern Era	2	2	2	6
Contemporary Era	2	2	2	6
Tomorrow Era	2	2	2	6
The Future	2	2	2	6
Arctic Future	3	3	3	9
Oceanic Future	6	6	6	18
Virtual Future	3	3	6	12
Space Age Mars	2	1	3	6
Space Age Asteroid Belt	2	1	3	6
Space Age Venus	2	1	3	6