Requirements: level 15+
In this event, you can open chests and receive guaranteed prizes from each of them.
There are 45 chests in total and rewards drop on a random basis.
 
 
The main reward is Art Academy of Latvia, size 8x7, can be placed anywhere
 
Every 24 hours: 4200 coins, 1-3 pearls, 1-3 energy


Each chest can be opened with 9 Summer Keys
There are 3 ways to get the Keys:

1. Completing quests
Key quests will appear one after the other in the menu on the left side
 

Handle the Lightning I
Collect 7 screw wrenches (in friends' cities)
Collect 9 fire extinguishers (Water Tower, Upgraded Water Tower)
Collect 7 reinforcements (Cargo Port) 

Handle the Lightning II
Ask friends for 6 repair kits
Collect 20 pencils (Stationery Shop, Upgraded Stationery Shop)
Collect 21 jugs (Bakery, Upgraded Bakery) 

Handle the Lightning  III
 Collect 17 valves (Premium Cottage)
Collect 22 pistons (Shoe Shop, Upgraded Shoe shop)
Collect 10 spools of thread (when you collect wool, tulle, denim, printed cotton, linen, Venetian lace, silk, velvet, lace from Textile Factories; when you collect wool, felt, cashmere from Upgraded Textile Factories) 

 
2. Collect profits from certain buildings:
Supertanic: 1 key every 24 hours
Windmill: 1 key every 18 hours
Round Church: 1-3 keys every 16 hours
Holyrood Palace: 2-3 keys every 24 hours
West Norway Museum of Decorative Art: 2-3 keys every 24 hours
 
3. Purchasing keys from a special offer
 
Unique offer: Holyrood Palacesize 10x9, can be placed anywhere
Every 24 hours: 4000 coins, 1-4 pearls, 1-4 energy, 2-3 keys during the promotion