The burial mound erected for Beowulf by the sea after his cremation is a barrow.
After Beowulf dies from wounds received while fighting the dragon, the Geats burn his body on a funeral pyre. They then construct a prominent mound, or barrow, on a headland beside the sea. The poem presents it as a lasting memorial that sailors can see from their ships and use as a landmark.
A barrow is an earthen or stone burial mound, a familiar feature of early medieval and prehistoric northern European landscapes. In Beowulf, the mound connects personal remembrance with public identity: it commemorates the dead king while displaying the Geats’ grief and pride to the wider world.
The answer is sometimes confused with a cairn, which is primarily a pile of stones, or with a crypt, which is an enclosed burial chamber. The poem’s English translations commonly call Beowulf’s monument a barrow, though translations may also use “mound” for the underlying Old English word.