Disabled groups say they are angry at the access for them at Swansea's £30m national waterfront museum.
The museum said 'valid issues' of disabled access had been raised
They have made a list of complaints, from the café and toilet facilities to the revolving entrance doors.
They have been consulted on the design and layout of the building for two years but claim much of what they suggested has been ignored.
The museum said valid issues had been raised but added the groups had visited the site before work was complete.
Llanelli and Neath Port Talbot disabled access groups have compiled a report on their findings.
Frank Allen, chairman of the Llanelli group, said: "I was asked to represent the physically disabled and have attended meetings in Swansea every month or so for more than two years.
"There were people representing all other different types of disabilities."
He said after their visit it was a unanimous vote that none of the group would permit the management to say they endorsed the building in any way.
"It was a sickening experience to go around it - one woman went home crying.
"We had given up our time and paid our own expenses."
Among the criticisms in the report is that the main entrance is accessed through revolving doors, with a side door for people with disabilities.
List of criticisms
"Disabled people should be able to enter through the same door as their friends and relatives," said Mr Allen.
"At the cafe, there was no way I could sit in the chairs as they were fixed to the tables.
Frank Allen said he had attended meetings for more than two years
"The self-service counter was so high from my wheelchair I could not get my hand over.
"There is no room in the toilet to transfer from your wheelchair."
The criticisms in the disabled groups' report include:
Use of glass of walls which could be a risk for the partially sighted
Handrails on stairs which are at an "uncomfortable height" for adults and on which children could bang their heads,
Door furnishings too high for wheelchair users and not easily visible
Non-uniform stair widths and little provision for people riding scooters or larger, powered wheelchairs.
"When we were asked more than two years ago for our input, we were very optimistic," added Mr Allen.
'Address points raised'
"We have been giving suggestions to them from the start but they have just blindly carried on."
The group accepts it was only shown two of the halls, work at the museum was ongoing and none of the exhibitions was in place.
In a statement, the museum said it had always had a "close dialogue" with the disability access groups and it aimed to have a "best practice building and exhibition" as far as access was concerned.
The statement read: "The visit of the access group did however raise some valid issues that can be used to improve access for all, although work to address the majority of the points raised was in hand prior to their visit.
"The timing of their visit to the unfinished museum allows the project team to respond to their list of concerns before the public opening this summer."