Portaferry is a small town in County Down, Northern Ireland, at the southern end of the Ards Peninsula, near the Narrows at the entrance to Strangford Lough. It is home to the Exploris aquarium and is well known for the annual Gala Week Float Parade. It hosts its own small Marina, the Portaferry Marina. The Portaferry – Strangford Ferry service operates daily at 30-minute intervals between the villages of Portaferry and Strangford, less than 1500 metres apart, conveying about 500,000 passengers per annum. It had a population of 2,514 people in the 2011 Census. The town is located within the Barony of Ards Upper.

County Down is one of the six counties of Northern Ireland, one of the nine counties of Ulster and one of the traditional thirty-two counties of Ireland. It covers an area of 961 sq mi (2,490 km2) and has a population of 552,261. It borders County Antrim to the north, the Irish Sea to the east, County Armagh to the west, and County Louth across Carlingford Lough to the southwest.