This is the dramatic moment a huge barge that had been wedged on rocks above Niagara Falls for over 100 years was dislodged during a storm and swept near the brink of the famous Horseshoe Falls.

US officials are monitoring the rusty iron boat - known as a scow - after it moved for the first time in 101 years, inching closer towards the 167ft (51 m) drop.

The barge had been grounded in shallow rapids near Niagara Falls on the Canadian side since 1918, but high winds and rain last Thursday dislodged the boat before it became trapped again.

The iron scow was considered immovable. Credit: AP

The Washington Post said the vessel was originally about a third of a mile from the brink of Horseshoe Falls, before was swept about 164ft (50 metres) downstream before becoming lodged again.

A Niagara Parks official said it could be stuck in its new location for days or even years.

According to NBC News, the scow broke loose from its tow during a dredging expedition in Canada's Niagara River on August 6, 1918. Two men, Gustav Lofberg, 51, and James Harris, 53, were on board at the time, but managed to prevent the barge plummeting over the edge of the falls, by opening the doors to flood the vessel which slowed it down.

They were rescued the following day but the boat was considered unsalvageable.