While Sir Edmund's widow, June, Lady Hillary, unveiled the plaque to open the centre at The Hermitage Hotel, Mr Ayres spoke on her behalf to a packed theatre in the building.
He believed Sir Edmund, who died in January, would have loved being at the opening, seeing old friends and having an opportunity to relive old times.
Describing the centre as "absolutely sensational", Mr Ayres said it was a great tribute to all those who created a place in which stories of the mountains could be told - stories of exploration, tourism, pioneering and adventure in the Southern Alps.
The opening was the culmination of vision, commitment, drive and passion - the same elements a climber used to climb a mountain peak - and Lady Hillary congratulated all involved in creating a wonderful facility, he said.
The $7.5 million centre, next to the hotel, outlines the area's history through the themes of transport, climbing and the Hermitage Hotel.
The Hillary Gallery is dedicated to the life and achievements of Sir Edmund and particularly his affiliation with Aoraki Mt Cook.
Yesterday's date commemorated the 55th anniversary of Sir Edmund's first ascent of Mt Everest and the 50th anniversary of the official opening of the third Hermitage Hotel - the first one was built in 1884.
John Davies, one of the hotel owners, said it was decided about seven years ago that since the region played such an important part in Sir Edmund's early climbing life, his association should be recognised.
The initial response from a modest Sir Edmund, when approached with the suggestion of a sculpture being commissioned, was that it should be of Harry Ayres, who taught him most of what he knew about technical climbing.
The bronze statue of Sir Edmund, unveiled in 2003, had proved popular with visitors from all over the world.
Mr Davies paid tribute to hotel manager Denis Callesen, whose "unbridled enthusiasm" for the project had been amazing.
To Mr Callesen's complete surprise, the theatre was announced by Mr Davies to have been named the Denis Callesen Theatre.
Pupils from Aoraki Mt Cook School performed a song at the opening, while Becky Murray sang some of the verses from a poem written by high country farmer Jim Morris about Sir Edmund's life.
The official ceremony was followed by a fly-past of ski-planes.
