Kibble Palace, a magnificent Victorian glasshouse in the city's Botanic Gardens, had been closed since September 2003.
Hundreds of people were involved in the project, which entailed dismantling the cast iron structure and computer tagging all the parts before dispatching them to Yorkshire for restoration.
Around 14,000 panes of glass had to be replaced, 200 massive tree ferns were replanted and goldfish from the pond were found temporary homes.
Eight large marble statues, which had graced the interior since the 1930s, also needed to be cleaned.
Kibble Palace was gifted to the city in 1873 by John Kibble, who shipped it to Glasgow by barge from his home near Loch Long. This time, it was transported to Yorkshire via the motorway by lorry.
The restored glasshouse will feature interpretative information panels on the history of the building and its botanical specimens and there will be a year-round programme of educational and cultural events.
An early proposal to create an education centre beneath the glasshouse had to be rejected because of the cost.
Louise Bustard, education officer for the Botanic Gardens, said: "As well as mounting exhibitions in the Kibble, the central area surrounding the tree ferns will be planted with examples of native ethno botany crops from different parts of the world. These will include plants that most of us have never heard of but which, for example, Aboriginal people in Australia have traditionally used as food."
Kibble Palace and the other public buildings in the Botanic Gardens will be open throughout the holidays, including Christmas Day and New Year's Day.