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 â 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.