The 54 life-size sculptures formed the eight-mile Go Go Gorilla trail around the city between July and September.
Individually-painted models could be found on pavements, in parks, shopping centres, on top of the castle mound and inside St John's Cathedral.
The trail, organised by the charity Break, ended on 7 September but on Sunday morning the gorillas came out of hibernation to go on public view outside The Forum.
Thousands of people queued to take one last look at each gorilla, which include homages to Freddie Mercury, Alan Partridge, Iron Man and a Transformer.
Go Go Gorillas will be kept on public display inside the Forum from Sunday evening until they are finally sold to the highest bidder on Thursday night.
Martin Green of Norfolk-based Break said he was amazed at the turn-out.
"This is the gorilla's final farewell and the weather has certainly helped today but I like to think the gorillas brought the sunshine to Norwich all summer.
"It's been amazing to see everyone's faces when they see them all together. Some of the artwork is really, really good and they deserve a closer look."
He added that Alanrilla, a gorilla with the human face of Alan Partridge, was proving the most popular with the Forum crowds.
It was created in just four days by artist Phil Daniels and his daughter Sam ahead of the fictional Norwich DJ's film premiere in the city in July.
Thursday's auction is a sell-out, with Break and the Born Free Foundation hoping to raise at least £2,000 for each fibre-glass sculpture.
It hopes to build on the success of Norwich's Go Elephant trail in 2008 which raised more than £200,000 for charities CLIC Sargent and the Born Free Foundation.
Break runs children's homes in Norfolk and Cambridgeshire and short-term breaks for children with disabilities.
Gorilla statues which graced the streets of Norwich this summer are being displayed together for the first time ahead of a charity auction.