The Slip Bridge was taken down in March 2004
Campaigners say over 150 people have objected to an order extinguishing a public right of way across a pedestrian bridge that was removed five years ago.
The Slip Bridge that spanned the main road on Swansea's foreshore was taken down because it was costly to repair.
It has been replaced by a pedestrian crossing at ground level and the city council wants to revoke the public right of way 20ft (6m) in the air.
The Open Spaces Society is among those arguing it may be needed in the future.
Until 2004 the bridge had stood on the foreshore for almost 100 years.
It was taken down for structural repairs but Swansea council decided it was too costly to put it back.
It now sits on the promenade but heritage campaigners hope one day it could be returned to its original site spanning the dual carriageway on Oystermouth Road.
The Open Spaces Society, which says it is Britain's oldest national conservation body, has objected to plans to officially close the public footpath.
It argues it may be needed in future.
The bridge had spanned the foreshore for almost 100 years
General secretary Kate Ashbrook said: "There are about 150 objectors to this plan, and we are backing them.
"Once the path is extinguished it is gone for ever and any hopes of restoring a bridge here are dashed.
"The current pelican-crossing is not a suitable alternative route.
"The Slip-Bridge path is a vital part of Swansea's maritime history. It should be celebrated, not extinguished.
"If we can save the route as a public highway, we can then argue for restoration of a safe crossing over Oystermouth Road, to provide access for walkers to the beach."
Swansea council said public consultation on the issue drew to a close on Monday.
It said it would now consider the responses it had received and if there were objections the matter would have to be settled by the Welsh Assembly Government.