Medals

Medals can be won in tournaments, after unlocking the corresponding towers in the world map. Their main purpose to unlock city extensions.  As development of the game has progressed, they can also be used to purchase blueprint pieces of the Great Buildings.
To win medals, you need to unlock the part of the  continent (in the world map) that contains it, then you have to fight and defeat your neigbours to gain points. Every Sunday, the tournament closes and winners obtain their medals, the amount of which depends on the age the tower corresponds to. You have to choose to attack neighbors, support them or do nothing with them. Dont choose nothing. For supporting you are given a token amount of 20 gold which is not much but when you do it 80 times thats 1600 gold which for the bronze are is tons of gold. After you get a steady stream of gold from residential buildings attack more and win the production of what ever they were making. They could be traded with Leonardo Da Vinci, for blueprints during this event (Feb 2013). Starting price was 20 medals per blueprint, and cost 20 more medals the next time.

Medal Scoring in PvP Tournament Tower

Rank	Bronze Age	Iron Age	Early Middle Age	High Middle Age	Late Middle Age	Colonial Age
1st	10	20	40	80	150	250
2nd	5	10	20	40	100	150
3rd	3	6	12	20	50	75
4th	2	4	8	12	40	50
5th	1	2	4	6	30	40
6th	-	-	-	4	25	30
7th	-	-	-	-	20	25
8th	-	-	-	-	10	20
9th	-	-	-	-	5	10
10th	-	-	-	-	-	-

The number of medals used to unlock a "victory expansion" increases the more of these expansions that have already been purchased (similar to forge point buying).  For example, the first expansion will cost 10 medals, while the second costs 50, and so on.