Question

what are the advantages of moat irrigation?

Answer 1

Moat or pulley-system: It is a manual irrigation method. By this method water is directly taken out of wells with the help of pulley and is used to irrigate fields...
it is cheaper or free of cost .
The advantages of moats in medieval times where that it made it extremely difficult for an attacking army to get into the castle. Castles usually had bridges that crossed over the moats so in times of war these gates would be raised up forcing the attackers to just generally lob boulders at the castle rather than foot soldiers running in and slaughtering everyone.