Birks is a Lake District fell of 624 m in Westmorland and Furness. It rises only 20.3 m above its key col, 3.3% of its height.
It sits below St Sunday Crag, only 1.5 km to the south-west and 217.2 m higher. Its key col leads to St Sunday Crag, not to its nearest higher summit, Gavel Pike. Its nearest higher summit, Gavel Pike (784 m, 1.2 km south-west), is a listed top not profiled here. The highest point is recorded as no feature: grass mound, not a cairn.