The Halifax Citadel Society — the group that does year-round reenactment living history at Citadel Hill — marked its 25th anniversary Saturday.

Over the past quarter century, the program has had many students working as part of the military reenactment group and guiding tours at the historic site. The society, a non-profit, charitable organization, runs the program in partnership with Parks Canada.

Celebrations included a presentation of new ceremonial battle flags, known as colours, to the 78th Highlanders. The last time new colours were presented was in 1999.

Parade Commander Kevin Andrecyk prepares to lead the ceremonial parade. (Danielle d'Entremont/CBC)

Rod MacLean, executive director of the Halifax Citadel Society, said for military units, it is seen as a "once in a generation" event.

People have come from all across Canada, some from as far away as British Columbia, for the reunion.

Halifax Citadel Society executive director Rod MacLean, right, watches Saturday's ceremonies. (Danielle d'Entremont/CBC)

Martin Ahern is one of the many alumni volunteers who came for the ceremony, and he knows quite a bit about the intergenerational importance of the event.

His dad worked in the military and served at the Citadel. He also met his wife while they were both working there, and now several of their children have worked for the Citadel as well.

The 78th Highlanders were presented with their new regimental colours. Members of the public and honoured guests watched this exchange of the ceremonial flags. (Danielle d'Entremont/CBC)

Ahern started the program as a summer job when he was just 18 years old in 1986, and has been involved ever since.

To him, the importance of the historical reenactments is bringing history to life, not just for tourists who come through but for Nova Scotians who might not know the piece of the province's history.

"There are people who live in the shadow of the Citadel, or probably any historical monument, and know very little about it. And books are only going to do so much in school."

Alumni of the reenactment program came to Halifax from all over Canada for the celebration. (Danielle d'Entremont/CBC)

Iain Summerby-Murray, the Colour Sergeant in charge of protecting the flags, said the colours are like the spirit of the regiment that is carried forward.

He said the ceremonies are definitely emotional for some of the people involved, especially because many of them would have been working for the Citadel when the last colours were presented 20 years ago.

He thinks the event is particularly special for the three men who presented the old colours in 1999, as all three of them were at the event Saturday to retire the old flags.

Members of the regiment marched away with the flags after they were blessed. (Danielle d'Entremont/CBC)

MacLean said the ceremony is poignant as it symbolizes the passing of the torch from past to future, while also paying tribute to all military units that have served at the Citadel throughout its history.

"It's kind of a mini history that's embodied in these flags," said MacLean. "It has a whole bunch of past associations and also has the whole idea of looking forward as well."