Campaigners are calling for a proposed new supermarket near a Unesco World Heritage Site to be rejected.
The site, near Conwy Castle in a valley to the south of the walled town, used to be a garage which closed in 2007 and was demolished in 2012.
People opposed to the plans for a Co-op said the "contemporary design" was not in keeping with the historical walled town.
The applicants said it would address the need for an extra convenience shop.
More than 100 separate objections have been lodged with Conwy council.
Conwy Town Council has "strongly objected" to the plans on the grounds Conwy is a Unesco World Heritage Site and "it would not be in keeping with the historic nature of the town and area".
One objector, Karen Bream, wrote to the council saying: "It will significantly detract from the visual impact of Conwy castle which Unesco considers to be one of the finest examples of late 13th and early 14th Century military architecture in Europe."
Town councillor Bill Chapman said: "It sits badly having a new supermarket on this site.
"A really modern new building does not go easily with the old town walls and the old buildings within Conwy town.
"We're not against business at all, as a council we support businesses, but this business, in this location, is wrong."
The Ancient Monuments Society also responded to the consultation and said: "The site currently, in its undeveloped form, allows for advantageous views of the castle.
"We believe that any development of the site should be used as an opportunity to enhance the setting of the World Heritage site and scheduled monuments.
"In its current form the proposal does not do this."
People in the area are also concerned about increased traffic and pedestrian safety on the roads nearby, as the main road between the site and the walled town passes through a narrow arch and has no pavement.
Natural Resources Wales also said it had "significant concerns" about the proposal in its current form.
Cadnant Planning said the proposed design had been subject to consultation with the council.
It said a recently completed library in the town showed how "contemporary modern buildings can work as a design approach alongside a World Heritage Site".
In the application documents, the company said: "The application has come forward to address an identified need for an additional convenience store to serve the communities of Conwy, Gyffin and Henryd.
"It is considered that the design of the new building has taken consideration of all key viewpoints and that the scheme will preserve and enhance the character of the area and the setting of heritage assets.
"The construction of the new store will improve local retail facilities and allow for increased choice and competition."