Barrows is a minigame that is located in mortiana.  it requires you to kill 6 brothers ~ Verac (cb115), Dharok (cb 115), Guthan (cb 115), Karil (cb 98), Torag (cb 115), Ahrim (cb98)  when you are doing the minigame,  you will have to slay 5 of the brothers and in the sixth brothers tomb there will be a message saying that there is a secret tunel.  if you accept to go forward it will take you to a crypt with a chest in the middle.  Search the chest and the final brother will appear and you must slay him.  when you have completed this you will search the chest again for your reward.  you will commonly get runes (blood, death, mind) and sometimes bolt racks or barrows equipment.  all barrows weaponry requires 70 att to wield with the exeption of Karils c'bow.  all barrows armour requires 70 def. to weild.