Twenty-five years ago she looked on as the Queen opened one of the greatest collections of world art accumulated by one person.

Yesterday, one-quarter of a century later, Winnie Tyrrell, 51, the longest-serving member of staff at the Burrell Collection, recalled the day the museum was unveiled to the public.

"The day we opened was unbelievable," she said. "The whole talk at the time was about the unveiling of the Burrell Collection and it was amazing to be a part of that.

"I am very proud to say I have seen many famous faces walk through the door over the years. Twenty-five years later I feel exactly the same about this spectacular collection of art, owned by one man.

"I think the time is right to concentrate on the refurbishment of this unique and beautiful building."

When Sir William Burrell and his wife, Constance, Lady Burrell, gifted his collection of more than 9000 works of art to Glasgow in 1944, the city became the world-renowned home of the famous collection.

Since the opening of the Burrell Collection in 1983 at Pollok Park, the status of the museum as an iconic part of Glasgow's culture has grown.

As museum staff looked back on the first 25 years, visitors wandering around the maze of medieval art, tapestries, alabasters, stained glass and English oak furniture had a rare chance to see the Burrell's prized collection of suzanis - richly embroidered wall hangings from Uzbekistan.

According to museum manager Muriel King, the importance of the collection as a national and international showcase is still key to its ability to attract visitors, but the future of the collection depends on more investment in the building itself.

"Looking ahead to the next 25 years, we'd like to continue to invest in the fabric of the building," she said. "The opening of the Burrell Collection signified Glasgow's cultural renaissance and we continue to attract millions of visitors. Maintaining the building and preserving the collection are the vision of the future."

I think that the time is right to concentrate on the refurbishment

The unique appeal of the Burrell allows young and old to marvel at the courtyard - home to the famous Warwick Vase, while also taking time to walk through the grounds of Pollok Estate. The building was voted second in the 100 best modern buildings of the past 50 years by Prospect magazine in 2006.

The design was chosen following a competition won by young architects Barry Gasson, John Meunier and Brit Anderson, who came up with a blueprint using large panes of glass in the walls and a roof that blurred the distinction between the building, sky and the surrounding woodland.

Bernard and Paula Flood watched the building being constructed when they lived close by 25 years ago.

"I remember watching the building going up," said Mr Flood. "Today we are here with our two-year-old grandson, but back then we were coming with his father. We find that when we are here we appreciate the outside as much as the inside. My favourite part of the Burrell Collection is the building itself."

Pupils from Hyndland Primary School were among the visitors celebrating yesterday's milestone birthday.

The P3 class were there to learn about knights and castles with their teacher, Mrs Simpson. "We take the primary three class here every year," she said. "It's a good way to teach them about history and art and the children love it."

As one of 12 museums run by Cultural and Leisure Glasgow, some onlookers feel the Burrell is lagging behind its counterparts and is in need of a makeover. The building won national recognition for its glass-based design, but recent problems with leaks in the roof have highlighted the need for refurbishment.

In 1999, museum boss Mark O'Neill promised the roof would be replaced within five years at an estimated cost of £2m, saying it was the number one priority after the refurbishment of Kelvingrove Art Gallery and Museum.

However, the work has never been carried out.

Liz Cameron, chairwoman of Culture and Sport Glasgow, said the future of the collection was in no danger of being jeopardised due to the poor state of parts of the building.

"A revamp is needed," said the former lord provost. "After 25 years there are parts of the building that need updating, but this is something we are looking at. I hope that over the next few years we will be able to look at plans to keep the collection and the building maintained."

In Profile

Sir William Burrell, who was born in Glasgow in 1861, was a successful shipping agent in Glasgow.

At the age of 14 he began working in the family firm of Burrell and Sons.

In 1885, on the early death of their father, William and his eldest brother, George, took over management of the family's firm. By 1918, the brothers decided to sell off almost the entire Burrell shipping fleet.

William Burrell invested his share of the proceeds shrewdly, and devoted the rest of his life to amassing the bulk of his art collection.

His interest in art began in his teens, and by 1900, he was an important and respected collector.

In 1944, Sir William and Lady Burrell signed the Deed of Gift of their collection to the City of Glasgow .

In 1967 Mrs Anne Maxwell MacDonald and her family gifted Pollok House to the city of Glasgow.

The site, in the corner of Pollok Estate, became the setting for what is known today as The Burrell Collection.