Surveying

hills= sapphire     woods= emerald    grassland= ruby     mountain=diamond  lake you cant survey.      several people have asked if surveying is a waste of time.  They could have left it out of the game but it can be useful.  You can survey while sleeping and it will not mess with your playing time.  Then when you have enough you can turn it in for something and it didn't cost you anything.   So how to survey - click your castle and go to wilds tab (far right may have different name) from here you can tap the coordinates for your wild and it will take you straight to the wild.   Reinforce it with 1 or more troops and once the reinforcement arrives a little shovel will appear to the left of the march tap it and survey will begin.  repeat until you have done all the wilds you wish to do.  Important Note: The higher the knight you use to reinforce with the faster the survey will go however if you do it while sleeping it wont matter.