Plans for Sydney Harbour Bridge-style climbs of the Forth Bridge have been revived, The Scotsman has learned.
Network Rail has applied for planning permission for a new centre at the south end of the bridge, from where parties of visitors would be led on to the 129-year-old structure.
It said the revived Forth Bridge Experience plans, six years after being unveiled, would offer “a unique and memorable visit to one of Scotland’s most loved and iconic structures”.
Groups of 12 to 15 people would don safety harnesses to tour the bridge’s south cantilever, or tower.
They would climb to a new viewing platform at the top, 367ft above the Forth, using walkways built into the structure.
Each tour is expected to last some two and a half hours.
Network Rail hopes the attraction will open in 2022/23.
However, estimated numbers taking part have been reduced to 85,000 a year from the 126,000 quoted when the plans were first mooted in 2013.
The scheme was subsequently put on hold because of changes to the way Network Rail is funded, with a “different type of business” needed.
Network Rail has kept on ice even more ambitious plans for a glass visitor centre and lifts at the northern end of the bridge that would take people to a viewing area at the top of the north cantilever.
It said such “longer-term plans” were still “under development”.
It had hoped to open at least one of the two schemes, originally estimated to cost a total of £15 million, for the bridge’s 125th anniversary in 2015.
The infrastructure body said: “This internationally acclaimed structure is considered one of the most ambitious and successful engineering achievements of the 19th century.”
Alan Ross, Network Rail Scotland’s director of engineering and asset management, said: “The Forth Bridge is an engineering icon.
“The plans we have submitted to deliver a bridge walk experience will offer a unique and memorable visit to one of Scotland’s most loved structures.
“From the engineering genius behind its design to the historical accounts of its construction and its crucial role in Scotland’s operational railway, the bridge really is a national treasure and there is real appetite to take these plans forward.”
A “bridge walk hub” would be created at a former works compound west of the crossing’s piers, north of Dalmeny station.
Network Rail said: “It will provide the space for visitors to undertake the necessary preparation for embarking on a bridge walk as well as providing the physical access to the bridge itself. Groups will arrive and check in and will then be taken into a briefing room where they will receive verbal and video instructions. They will then move into a changing area to receive safety clothing and harnesses
“Accompanied by a guide, groups of around 15 walkers will then exit on to the roof of the building to climb up a ramp to an upper level and then on to the bridge itself.
“Walkers will wear a harness, which will be attached to a continuous running safety line starting at the foot of the access ramp.”
Paul Tetlaw, of sustainable transport campaigners Transform Scotland, said: “The plans by Network Rail are to be welcomed and there is no reason why the bridge walk won’t become as popular as those to the Sydney Harbour Bridge and the O2.
“The southern approach to the bridge is well served by the station at Dalmeny and so I’d expect Network Rail to encourage bridge visitors to arrive by train.”