It began life a quarter of a century ago as an event to fill gaps in the schedule at Glasgow’s new Royal Concert Hall during the quietest spell of the year in the city.
More than 32,000 traditional music fans flooded into the venue at the top of Buchanan Street for an event promoting Glasgow as “the warmest place to be in January.”
By the second year it already burst out of the venue and was soon spreading to concert halls across the city.
When the 25th programme, which has been unveiled by the festival director Donald Shaw, gets underway this January it will boast more than 300 events across 26 stages.
The line-up includes an expansion to the Pavilion Theatre for the first time and one-off Saturday night shows in both the Hydro arena and the Barrowland Ballroom.
The festival will also mark its big birthday party by staging a “synchronised live music session” with more than 20 countries around the world.
Highlights of the next year’s line-up include a special appearance from stunt cyclist Danny MacAskill, who will ride a recreation of a mountain range in his native Skye at the Hydro, concert honouring the back catalogue of American singer-songwriter Tom Petty, who died earlier this month, and a 20th anniversary celebration of the community buy-out of the Isle of Eigg.
The Pavilion will be hosting three special shows celebrating the life and legacy of the Bard of Dundee, Michael Marra, the sing-songwriter who passed away five years ago this month, an evening with west coast “ceilidh king” Fergie MacDonald, who has just turned 80, and Hebridean favourites Skipinnish.
The festival will be celebrating with acts marking their own anniversaries, including 25 years of Big Country, 30 years of The Levellers, 20 years of Blazin’ Fiddles and 50 years of the Tannahill Weavers.
A host of audience favourites from the last 25 years, including Eddi Reader, Julie Fowlis, Sharon Shannon, Lau, Peatbog Faeries and Kate Rusby have been lined up for the 18-day event, along with rising stars Ryan Young, Siobhan Wilson, Roseanne Reid, Fara, Tide Lines, Elephant Sessions and Iona Fyfe.
Former Celtic Connections favourites The Humpff Family and Croft No Five will be reunited for the birthday celebrations, while the line-up includes Dougie MacLean and Brian Kennedy, who both played the first festival in 1994.
Big names from the Scottish indie music scene gracing next year’s event include King Creosote, James Yorkston, Eugene Kelly, Broken Records, Roddy Woomble and Roddy Hart, while Scottish jazz stars Brian Kellock and Tommy Smith will also be performing.
American acts lined up include singer-songwriter Shawn Colvin, Sara Watkins and Sarah Jarosz, and the bands The Mavericks, Lord Huron and The Lone Bellow. The overseas contingent will also include Congolese superstar Jupiter Bokondji, the Afro-Cuban All Stars, Mali singer Oumou Sangare and Finnish band Frigg.
The festival has dusted down down its archives to recall the surprise and cynicism that greeted news that Glasgow was launching a new festivall in the depths of winter - including among musicians.
Shaw, whose band Capercaillie played the early festivacls, said: “I thought it was a very strange thing to do myself. I thought it would lose a lot of money, die a death and never be heard of again.
“I really felt that the next festival needed to have a sense of what has gone on over the last 25 years, but that it can’t just be a nostalgic trip. The festival has moved on so much, and the attitude of musicians is so much more progressive than when the festival started.
“The audience pull for bands like Manran, Skipinnish, Skerryvore and Tide Lines is enormous now.”
The biggest show in the 25th birthday line-up will see a reunion for the Grit Orchestra, which was instigated by Mr Shaw and the violinist Greg Lawson to open Celtic Connections two years ago with a live recreation of the late musician Martyn Bennett’s final acclaimed album. They will tackle another Bennett album, Bothy Culture, in the Hydro, with a special appearance from MacAskill, who used his music on his famous video filmed in the Cuillins.
Mr Shaw said: “We’ve taken the Bothy Culture album as the starting point for almost turning the Hydro into a club.
“I wanted to have other elements that were quite special. Ever since I saw the video of Danny cycling across the Cuillins against the backdrop of Martyn’s music I kind of wondered what was plausible. It was like watching dance. It wasn’t so much about shock and awe, it was the gracefullness of what he was doing.
“When we met he felt it was a slightly crazy idea, but also really exciting. It’s the first time he has ever done anything in synchrony with live music. We’re going to be using the full height and width of the Hydro for the set we’re building. Let’s just say he is going to be above the orchestra at certain points.
“Ultimately it will be a statement about where Celtic Connections has come from and the ambition of the festival.”
The 25th Celtic Connections runs from 18 January-4 February.
25th Anniversary Concert: Eddi Reader, Cherish The Ladies, Sharon Shannon and Kris Drever are among those getting the party started at the Royal Concert Hall.
Roaming Roots Revue: Roddy Hart’s indie-folk centrepiece of Celtic Connections pays tribute to late American songwriting legend Tom Petty, with the all-star cast including Cory Chisel, Pictish Trail, Natalie Prass and Joel Plaskett.
Isle of Eigg 20th Anniversary Ceilidh: Although the Hebridean island’s “independence day” is in June, the festivities in Glasgow will include some of its most popular musical performers from its hugely popular dances and festivals.
Fergie MacDonald: The accordion legend will be discussing his career and joining forces with some of his regular collaborators, including Allan Henderson, Phil Cunningham and Iain MacFarlane as the Pavilion makes its debut in the Celtic Connections programme.
Arrest This Moment: Author James Robertson, who has just published a biography of Michael Marra, oversees a new stage show featuring guest musicians Karine Polwart, Rab Noakes and his son and daughter Chris and Alice.
Skerryvore/We Banjo 3: The famous Barrowland Ballroom dancefloor is expected to be tested to the full with a double bill of the Hebridean and Irish outfits, two of Scotland’s most reliable festival crowd-pleasers.
Celtic Connections Global Session: A synchronised “live and online interactive music session” is planned to unite musicians in Glasgow with counterparts in more than 20 countries, including France, Spain, Italy Germany, Brazil, the US and Canada.
Songs of the Gael: The BBC Scottish Symphony Orchestra will perform with a host of Scotland’s best-known Gaelic singers, including Julie Fowlis, Karen Matheson, Robert Robertson and Mischa Macpherson.