U 1014 is the Rundata designation for a Viking Age memorial runestone that is located in Ärentuna, which is about one kilometer east of Lövstalöt, Uppland, Sweden.
The inscription for stylistic reasons has been attributed to the runemaster Öpir, who was active in the Uppland area in the late 11th or early 12th century.
This runestone style is characterized by slim and stylized animals that are interwoven into tight patterns.
The animal heads are typically seen in profile with slender almond-shaped eyes and upwardly curled appendages on the noses and the necks.
The runic text states that a man named either Holmgeirr or Hjalmgeirr raised the stone as a memorial to his two sons, Ígulfastr and Svarthǫfði.