Liverpool mayor Joe Anderson has personally blocked plans for a £5m aerial zip wire in the city.
In June, councillors backed Zip World's proposals for a 400m (1,300ft) line running from St John's Beacon to Liverpool Central Library.
However Mr Anderson said he had "serious concerns" about using a council-owned building for the project.
Zip World co-founder Sean Taylor said it was a "setback", but the firm still had "a big future" in Liverpool.
Mr Taylor had claimed the attraction would boost tourism and create jobs.
But objectors argued that the zip wire, which would pass over St John's Gardens behind St George's Hall, could lead to the "Disneyfication" of the city centre.
Mr Anderson said the city's planning committee had acted "fairly and democratically" in granting the application despite the objections.
"As mayor, I do not interfere in the planning process," he said.
"However, I do have the final decision on whether a building owned by the council should be used in such a way.
"I have serious concerns about using this area and, having spoken to the company, could not let them progress further, knowing I would not support it."
Analysis - Claire Hamilton, Political Reporter, BBC Radio Merseyside
Mayor Anderson (pictured above) is known for his forthright style of leadership - it was his decision to remove the city's bus lanes six years ago, for example.
He wouldn't normally intervene directly in a planning decision - but this particular issue has drawn negative press from across the country, and the threat of a legal challenge, which could prove costly if the council lost.
It's often hard to balance the value of Liverpool's heritage with the demands for investment and progress, but this might be a case of the Mayor picking his battles, bearing in mind the ongoing concerns about Everton's new stadium and the city's UNESCO World Heritage status.
It seems the council and Zip World are working together to find a new venue for the project, but Central Library was obviously a step too far.
Mr Anderson thanked Zip World for their co-operation and said the city would always try to support "imaginative ideas".
"I have today informed them that I will not give permission for any council-owned building in this area to be used for the zip wire.
"They have accepted my position and we have mutually agreed to work together to identify an alternative option."
Mr Taylor said his firm respected the mayor's decision "and we remain committed to working with him and Liverpool City Council to find a new landing point".
"Yes, this is a setback, but we are pressing ahead with our plans [and] I am sure there is a big future for Zip World in Liverpool."