There is a Neolithic chambered cairn in the southwest overlooking Calf Sound, which separates the island from Eday.

Rectangular in shape, the cairn was excavated in 1936–37 and contains a small chamber with two compartments and a larger one with four stalls that has a separate entrance and was probably added at a later date.

[6] From the 17th to the 19th centuries, the Calf of Eday was home to a salt works,[10] the remains of which can still be seen to the north of cairns.

[7] "Eday" is a name derived from the Old Norse eið and means "isthmus island".

[16] The island has been designated an Important Bird Area (IBA) by BirdLife International because it supports breeding seabirds.