It’s probably best if you gird yourself before you look down from the Arouca Bridge

The narrow footbridge suspended across a river canyon in northern Portugal claims to be the world’s longest pedestrian bridge and was officially inaugurated on Sunday.

The Arouca Bridge offers a half-kilometre walk across its span, along a metal walkway suspended from cables.

Some 175 metres below, the Paiva River flows through a waterfall.

Arouca is 300 kilometres north of Lisbon, the Portuguese capital.

Local residents got a first walk on the bridge last week. Many were thrilled — even as some admitted it was a little unnerving to feel so high up and exposed.

Guinness World Records says the world’s longest suspension bridge for pedestrians is Japan’s Kokonoe Yume Bridge, which opened in 2006 and spans 390 metres.

But the Charles Kuonen Suspension Bridge, which opened in the Swiss Alps in 2017, challenges that mark at 494 metres.

The Arouca Bridge cost 2.3 million euros (£2 million) to build.

Children under six are not allowed on it and all visits will be accompanied by guides.

Access costs between 10 and 12 euros (£8.70-£10.40) and must be booked through a local website.