Strangford Lough

Strangford is the largest sea lough in the British Isles, about a hundred and fifty square kilometres, connected to the Irish Sea by a narrow channel called the Narrows where the tide runs at up to eight knots; the name comes from Old Norse for strong fjord. In 2008 SeaGen, the first commercial-scale tidal turbine in the world, was installed in the Narrows and ran for eight years before removal. The lough is dotted with at least seventy islands and many smaller islets, or pladdies, most of them drowned drumlins left by ice, giving the rounded egg-shaped humps that define the landscape. It is a marine nature reserve where common seals and basking sharks are found, and about three quarters of the world's light-bellied brent geese, often up to 15,000 birds, winter here.

What you'll find

• The drumlin islands - at least seventy drowned glacial hills in the water.
• The Narrows - a tidal channel running at up to eight knots.
• The seals - common seals hauled out on the rocks and islands.
• The brent geese - a large share of the world population wintering here.

When to go

April to October for boats and walking; October to March for the brent geese, which arrive from Arctic Canada. Seals are present year-round with pups in summer. The Portaferry ferry runs frequently through the day.

Things to know

The lough is large and the road around it is long, so a car and time are needed. Tidal currents in the Narrows are dangerous for small craft and swimming. Many of the islands are private or protected and cannot be landed on.

Nearby

Mount Stewart is on the eastern shore; Downpatrick and the Mournes lie south.

Key facts