At 345 metres long, 3 metres wide and 80 metres high, the bridge, in Ardabil province in north-western Iran , is thought to be the largest construction of its kind in the Middle East.

It is set over the Khiavchai River next to the city of Meshgin Shahr, in a region of the country that has been noted for its potential for tourism development.

The bridge is next to the city of Meshgin Shahr, which has a population of about 65,000. (Photo: Mehr News Agency/Taher Hazrati)

The building of the bridge, whose cost is estimated at $40 million, was resumed recently after a six-year break, according to news website Real Iran.

The bridge spans one of Iran's many green valleys. (Photo: Mehr News Agency/Taher Nazrati)

Telegraph Travel’s contacts in Iran could not confirm exactly when visitors would be able to use the bridge to cross the valley, but It is expected to open in the next week or so.

The bridge has been under construction for at least six years. (Photo: Mehr News Agency/Taher Hazrati)

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According to the news website Real Iran, a “tourist town” comprising of hotels, spa pools, skiing, horse riding, chariot racing and cycling is to be built next to the bridge. The city council website is currently showing photos of the “tourism development” construction works.

The bridge is next to an area tipped for tourism development. (Photo: Mehr News Agency/Taher Hazrati)

A paper presented at the World Geothermal Congress in Australia this year described Meshgin Shahr’s hot springs as “a fantastic opportunity” to develop an “ international destination for natural spa tourism.”

There are already at least three spa complexes in the region, and Meshgin Shahr is one of the main hopping off points into the dramatic Sabalan mountains of north-western Iran. The city itself also has numerous tourist attractions, including a castle, petrographs, and the tomb of Shaykh Haydar, a leader of a Sufi order in the 15th century.

• Iran: the new must-see destination?

The Shaykh Haydar tomb is one of Meshgin Shahr's attractions. (Photo: Wikipedia/Alireza Javaheri)

Iran is making attempts to welcome more international visitors: Masoud Soltanifar, director of the Cultural Heritage, Handicrafts and Tourism Organization, has previously stated an aim to attract 20 million tourists by 2025, and earn $30 billion annually from the industry.

Meshgin Shahr is near the Sabalan mountains. (Photo: Mehr News Agency/Taher Nazrati)

The British Foreign Office still advises against all but essential travel to the country, partly because the embassies in Tehran and London have been closed since 2011. A number of British tour operators offer trips to the country, however, with some venturing into the lesser-known north-western region. Persian Voyages offers an 18-day tour, "Travels through space and time" that travels through Meshgin Shahr and visits the lands of Iran's nomadic populations, including the Qashqai.