Mount Leinster (Irish: Stua Laighean) is a 794-metre-high (2,605 ft) mountain in the Republic of Ireland. It straddles the border between Counties Carlow and Wexford, in the province of Leinster. It is the fifth-highest mountain in Leinster after Lugnaquilla 925 metres (3,035 ft), Mullaghcleevaun 849 metres (2,785 ft), Tonelagee 817 metres (2,680 ft), and Cloghernagh 800 metres (2,600 ft), and the highest of the Blackstairs Mountains. A 2RN transmission site tops the peak with a mast height of 122 metres (400 ft).