Tonelagee is a Hewitt of 815.8 m in Wicklow. It stands 175.8 m above its nearest neighbour, Scarr, 4.8 km to the east.
Of the register hills in Wicklow, only Lugnaquillia Mountain and Mullaghcleevaun stand higher. Of the 7 register hills in Wicklow, it has the smallest drop. On the Hewitts height ladder it sits between The Cheviot (816 m) and Mweelrea (814.5 m).