It is dedicated to Ia of Cornwall, a 5th- or 6th-century Irish saint, and is a Grade I listed building.

[1] The church is dedicated to Ia the Virgin, also known as Ives, supposedly an Irish holy woman of the 5th or 6th century.

The current building dates to the reign of King Henry V of England.

An outer south aisle was added by the Trenwith family about 1500: this is now the Lady Chapel and contains a statue by Barbara Hepworth.

There is a late medieval lantern cross, ten-and-a-half feet high on an octagonal shaft.