Illgill Head is a Lake District fell of 608.8 m in Cumberland. It is one of the 39 Wainwrights that are also Marilyns.
On the Wainwrights height ladder it sits between High Seat (609 m) and Seathwaite Fell (Wainwright summit) (601.1 m). The highest point is recorded as rock, not a cairn.