Where do these horsemen come from?

[Aceman]

Sorry, this is a noob question, but I cannot find the answer when googling. Have been playing this game for a couple of days now. Attacking mainly Classical Age bases now, while I am Iron still myself. Shortly after initiating the attack in Classical, horsemen show up apparently from nowhere. Seem to spawn from the edge of the base. Are they Alliance troops? Will they appear where ever I put my troops?
Any help appreciated!

 

[This game is laggy]

It's from a library research that provides up to 4 defenders from the forest: http://dominations.wikia.com/wiki/Reinforcements

You get to build library in Classical age..

 

[firedancer]

The Horsie men comes from the forest to aid your defense. They are like Riders of Rohan from LOTR movies.

 

[Tufqifo]

Lol! Both great answers! As for where they come out, it appears to be random. Sometimes they are on top of my troops immediately, and other times they have to cross the whole town! And hey, noob questions are what this page is all about!

 

[Aceman]

Thanks guys. Makes sense. One more hour and my town hall is Classic. Ill build that library pronto.