On an outside wall of Londonderry's Tower Museum hangs a blue plaque in honour of Mabel Remington Colhoun.
It remembers the many and varied achievements of an archaeologist, teacher and historian to life in the north west.
But, throughout a life less ordinary, she was also a prolific photographer.
Now a collection of her previously unseen photos has been digitised and made available online for the first time.
Digitising the photographs - which had been in storage since the early 1990s - has been" a journey of discovery" for Tower Museum volunteer Denise Henry.
For the past three years she has been scanning some of the 10,000 slides left to the museum after Ms Colhoun's death in 1992.
"What lay in boxes were the remains of a full and fascinating life. Like an archaeological dig there were many layers to uncover," she said.
Ms Colhoun's photos span much of the 20th Century - a chronicle of life in Derry and Inishowen, in County Donegal, and of the people, places, heritage and history, that in part shaped a city and its hinterland.
They are part of the wider Mabel Colhoun Collection bequeathed to the Derry museum.
The photographs, Denise said, are a "visual time capsule" that complements the other material in the Colhoun archive.
Who was Mabel Colhoun?
- Mabel Remington Colhoun was born in Derry in 1905.
- Her family came from the Malin area of Inishowen, County Donegal.
- For decades Mabel voluntarily researched and recorded the Inishowen landscape.
- A pioneering archaeologist, her published work - The Heritage of Inishowen: Its Archaeology, Heritage and Folklore - is still held in high regard.
- An educationalist, she started a preparatory school in her home in Deanfield, Derry.
- In 1935, she became the first principal of the preparatory department of Londonderry High School, where she worked as a teacher until her retirement in 1969.
- After her death in 1992, Ms Colhoun's collection of artefacts, documents and ephemera was donated to the museum. They have since featured in numerous exhibitions and been fully catalogued by the West Inishowen History and Heritage Society.
They include pictures of the opening of Derry's Craigavon Bridge in 1933, the arrival of Italian General Balbo to the city, during World War Two, the Queen's coronation visit to Northern Ireland in 1953 and the building of the Foyle Bridge.
Her archaeological work is well documented too, as are the land and seascapes of Inishowen and its coast, while a series of sketches showcase her love of the natural world.
Denise, who was introduced to Mabel Colhoun when studying archaeology, said it is fitting her images have now gone on display.
"Little did I know when I opened a book called The Heritage of Inishowen: Its Archaeology History and Folklore that I would begin a lifelong project to learn about and promote its author, Mabel Remington Colhoun," she said.
"Mabel was an educator, someone who wants to always share her findings. That's what she did with these slides."
Her work on the images, she added, has been "a pleasure".
"I never met her though I would have loved to. From talking to those that did, it shines through that she really wanted to inspire people," she said.
The images are now available online at the Tower Museum's website.
They're only "a small reflection" of the collection, the museum's education officer Ronan McConnell said.
He said many capture a city and a rural Ireland now consigned to history.
Ms Colhoun, he added, was "a pioneer".
"She would carry out roles not normally associated with women and was quite simply the best at it, widely recognised as an archaeologist, teacher, photographer, and naturalist," he said.