What are some major battles in Beowulf?

As is typical of heroic epic, the main theme of Beowulf is that of a hero proving his virtue and his valor by defeating enemies in battle. The first battles in Beowulf's life were actually with the sea monsters he encountered during a swimming contest with his childhood friend Breca.
Next, the monster Grendel attacks the mead hall Heorot routinely over a period of twelve years. Beowulf comes to the aid of King Hrothgar and has an epic fight against Grendel in which he manages to rip off Grendel's arm, a wound that proves fatal. 
Grendel's mother, angered and grief stricken by the death of her son, then attacks the mead hall. Beowulf manages to follow her back to her lair and kill her.
The final battle of the poem is the one against a dragon. Beowulf kills the dragon but takes a mortal wound and dies in the process.