Torfaen is a county borough in the south-east of Wales. Torfaen is bordered by the county of Monmouthshire to the east, the city of Newport to the south, and the county boroughs of Caerphilly and Blaenau Gwent to the south-west and north-west. It is within the boundaries of the historic county of Monmouthshire, and between 1974 and 1996 was a district of Gwent, until it was reconstituted as a principal area in 1996.