Courtesy Stephen Clarke
Grandpa's photos - the Peak, Hong Kong -- 1960s: Dave Tomkins' grandfather Stephen Clarke traveled the world in the 1960s, photographing sights and scenes from his travels -- including the Peak in Hong Kong, pictured.
Courtesy Dave Tomkins
Grandpa's photos - the Peak, Hong Kong -- present day: Tomkins stumbled across Clarke's travel photos in 2009 -- he was clearing out his grandfather's house following Clarke's move to a nursing home.
Courtesy Stephen Clarke
Grandpa's photos -- Top of the Empire State, New York, USA -- 1960s: Inspired, Tomkins decided to investigate the stories behind the photos.
Courtesy Dave Tomkins
Grandpa's photos -- Top of the Empire State, New York, USA -- present day: He scanned in the slides and showed his grandfather, but Clarke didn't remember where the photographs were taken.
Courtesy Stephen Clarke
Grandpa's photos -- Tejo River, Lisbon, Portugal -- 1960s: Tomkins remained struck by the variety of places his grandfather seemed to have visited.
Courtesy Dave Tomkins
Grandpa's photos -- Tejo River, Lisbon, Portugal -- present day: He was also surprised by the quality of the images and their careful composition.
Courtesy Stephen Clarke
Grandpas photos -- Kowloon bus station, Hong Kong -- 1960s: In 2014, Tomkins started a website Grandpa's Photos, harnessing the worldwide online community to pinpoint the locations in each image.
Courtesy Dave Tomkins
Grandpas photos -- Kowloon bus station, Hong Kong -- present day: He scanned in 50 of the slides and asked people to help track down the location.
Courtesy Stephen Clarke
Grandpa's photos -- Mrs Macquarie's Chair, Sydney Australia -- 1960s: The idea stemmed from Australian Tomkins ability to recognize Sydney Harbour, pictured here.
Courtesy Dave Tomkins
Grandpa's photos -- Mrs Macquarie's Chair, Sydney Australia -- present day: "It made me realize that all I have to do is get these photos in front of as many people as I can and someone is going to know where they are," Tomkins said.
Courtesy Stephen Clarke
Grandpa's photos -- Romano's, Burrano, Italy -- 1960s: The project became a way for Tomkins to connect with his grandfather, pictured center, and celebrate his life and legacy-- particularly after he passed away in 2013.
Courtesy Dave Tomkins
Grandpa's photos -- Romano's, Burrano, Italy -- present day: Clarke, pictured center recreating the Italian restaurant scene, says people have responded to the familial message at the heart of the project: "Anyone can relate to it I think."
Courtesy Stephen Clarke
Grandpa's photos -- Aare River, Olten, Switzerland - 1960s: Following the huge response, Tomkins began retracing his grandfather's footsteps and retaking the photos.
Courtesy Dave Tomkins
Grandpa's photos -- Aare River, Olten, Switzerland -- present day: Seeing scenes move from photograph to reality is always special for Tomkins. "Walking into this scene that you've been staring at for five years is just amazing," he says.
Courtesy Stephen Clarke
Grandpa's photos -- Central District, Hong Kong -- 1960s: Following in his grandfather's footsteps was both fulfilling and surreal for Tomkins: "I can imagine he went for a little stroll with his camera and I retraced the journey he went on which was pretty cool for me to do," he says.
Courtesy Dave Tomkins
Grandpa's photos -- Central District, Hong Kong -- present day: To date, Tomkins has had more than 800 emails from people offering their thoughts on where his grandfather's photographs were taken.
Courtesy Stephen Clarke
Grandpa's photos -- Nathan Rd, Hong Kong -- 1960s: Tomkins says people love helping him solve the mystery behind the photographs. "They really enjoy being the person who can know a place or can point out a place and I think that really drives people."
Courtesy Dave Tomkins
Grandpa's photos -- Nathan Rd, Hong Kong -- present day: For maximum authenticity, Tomkins even used the same camera Clarke used in the 1960s -- a Voigtlander Bessamatic.
Courtesy Stephen Clarke
Grandpa's photos -- Via Alcide De Gasperi, Sarezzo, Italy -- 1960s: Even with the help of people across the world, Tomkins sometime struggled to find the exact location, as in the case of this Italian scene.
Courtesy Dave Tomkins
Grandpa's photos -- Via Alcide De Gasperi, Sarezzo, Italy -- present day: After hiking for four hours with no luck, Tomkins stumbled across the view unexpectedly. "I walked around the corner and there it was," he recalls.
Courtesy Stephen Clarke
Grandpa's photos -- Le vele di vanezia, Venice, Italy -- 1960s: Tomkins particularly enjoyed exploring Venice. "People told me exactly where [the locations] were," says Tomkins. "But it's such an intricate little maze of a place."
Courtesy Dave Tomkins
Grandpa's photos -- Le vele di vanezia, Venice, Italy -- present day: Getting lost in Venice allowed Tomkins to imagine what his grandfather experienced: "I almost got to follow Grandpa as he walked around and discovered places in that maze," he says.
Courtesy Stephen Clarke
Grandpa's photos -- The Ritz Hotel, Lisbon, Portugal -- 1960s: "This is such a cool thing for me because I get to talk about Grandpa and learn about him and tell people about him all the time," says Tomkins.
Courtesy Dave Tomkins
Grandpa's photos -- The Ritz Hotel, Lisbon, Portugal -- present day: Now there's only one photograph left to decipher -- and Tomkins has mixed feelings about the project coming to a close.
Courtesy Stephen Clarke
Grandpa's photos -- The Peninsula Hotel, Hong Kong -- 1960s: Tomkins loves that his project keeps the memory alive. "It almost feels like he's still out there somewhere."
Courtesy Dave Tomkins
Grandpa's photos -- The Peninsula Hotel, Hong Kong -- present day: But this means the end of the project will be bittersweet.
Courtesy Stephen Clarke
Grandpa's photos -- Piazza Nicola Demidoff, Florence, Italy -- 1960s: Tomkins says that when all the photograph locations are identified, it will feel like "there's nothing more to keep talking about."
Courtesy Dave Tomkins
Grandpa's photos -- Piazza Nicola Demidoff, Florence, Italy -- present day: But thanks to Clarke's striking photographs -- and the journey they've inspired for his grandson and people across the world -- Clarke's memory will live on.
CNN  — 

Back in the summer of 2009, while clearing out his grandfather’s house after he had moved into a nursing home, Dave Tomkins came across a box, the contents of which would eventually take him on adventures to 17 cities in seven countries and lead Internet users on a photographic treasure hunt.

The box he found in the house in New South Wales, Australia, was filled with 50 photographic slides, showing his grandfather Stephen Clarke’s travels across Europe, the United States and Asia during the mid-1960s, journeys that Tomkins knew nothing about.

GALLERY: See Tomkins’ recreations of his grandfather’s photos

Unexpected discovery

Courtesy Stephen Clarke
Stephen Clarke, pictured, traveled the world as a young man and took many photographs along the way.

Holding the small 35mm sized images up to the light for hours, Tomkins who works as an Art Director was amazed, not only at the composition and quality of the images, but also that his grandfather had traveled extensively at all in a time when air travel to Europe from Australia was lengthy and expensive.

“As we always do when we are five, and six and 10, we go to our grandparents and try and tell them how wonderful we are, how well we’re doing at school and at soccer” says Tomkins.

Courtesy Stephen Clarke
Tomkins came across the box of slides, including this one of Venice, whilst clearing out his grandfather's house.

“You know I spent way too much time talking about myself and never really asked grandpa about what he got up to, which feels a little silly now. So, when I saw the slides I was really interested in where the hell he went and what he got up to.”

In the nursing home, his grandpa was feeling pretty down so Tomkins thought the slides would offer something for them to talk about and cheer him up. Scanning them onto his laptop, Tomkins did a big reveal of the photos but Clarke did not share his enthusiasm.

“He wasn’t really interested. He couldn’t remember and didn’t want to talk about it that much” explains Tomkins.

In July 2013, Clarke passed away and Tomkins never did find out where exactly his beloved grandfather had traveled.

Photography quest

Courtesy Stephen Clarke
Tomkins grandfather took this photo of Sydney Harbour when the iconic Opera House was still being built.

Of the 50 slides he found, there was one that he recognized as showing the Sydney Harbour Bridge and the half-built Opera House.

And that got Tomkins thinking.

“I looked at that photo and I knew instantly where it was because I’m from Australia. What that kind of made me realize is if I know where that is and it’s not even built yet, someone in Italy is going to know where that bridge is, it made me realize that all I have to do is get these photos in front of as many people as I can and someone is going to know where they are.”

Courtesy Dave Tomkins
Tomkins recreated the Sydney harbor image.

In 2014, Tomkins who had spent years thinking and talking about putting the photos online to track down where they were taken, quit his job and built a website showcasing them.

Within a week of the launch, 45 of the 50 locations featured had been identified, and not necessarily by those who immediately knew where the place was.

“People love the mystery” says Tomkins.

“They really enjoy being the person who can know a place or can point out a place and I think that really drives people. One guy sent me an email that had 20 Google Street View links in it. The amount of work behind that is insane.”

Family values

Courtesy Stephen Clarke
The project has become a way for Tomkins to explore his grandfather's life and legacy.

He also received a huge number of emails from those who simply wanted to talk about family.

“Forty percent of the emails I get are people saying ‘sorry I don’t know where any of the photos are but…’ and they want to talk about their grandpa.

“A lady from Serbia emailed me with a really heartfelt message about how she got on the website and started crying and then called her dad who she hadn’t spoken to him in 20 years.

“I think that’s what’s really cool about this, is people move on to the story of their grandparents or parents. Everyone can relate to it I think.”

On the road

Courtesy Stephen Clarke
Tracking down the locations of the photographs isn't always easy -- this Italian scene proved tricky to recreate.

Following the huge response, Tomkins decided to spend the next two months retracing his grandpa’s footsteps, standing where his grandfather stood and retaking almost all of the photos using the same camera Clarke had used in the 1960s – a Voigtlander Bessamatic.

Sometimes he would arrive in a country knowing exactly where the destination was, other times he would have to hunt around but the end result was always worth it.

“In Italy, I was staying in a hostel and I had to get a bus, a train, and another bus into the hills to Sarezzo. It was really hot and I had four cameras and a tripod and all this gear and I hiked around for hours and hours trying to find this one photo and I didn’t find it.

Courtesy Dave Tomkins
Eventually Tomkins stumbled across the Italian view unexpectedly.

“I got really down, and thought I’ve made all this effort and I’m not going to find it, sorry grandpa I tried. Then I had to walk back down the hill to get the bus and I walked round the corner and there it was.

“Walking into this scene that you’ve been staring at for five years is just amazing. I imagined grandpa standing there with his Voigtlander and taking a photo and then I got to do the same thing.”

Following in his footsteps

Courtesy Stephen Clarke
Clarke -- and later Tomkins -- traveled around the world, including to Hong Kong.

In some places, retracing his grandfather’s footsteps was a surreal experience for Tomkins.

“The photos in Venice were really interesting because people told me exactly where they were but it’s such an intricate little maze of a place so I almost got to follow grandpa as he walked around and discovered places in that maze.

“The photos seemed really far apart before I got there but I spent all day in St Mark’s Square trying to get the light to match up and then I walked around the corner following the directions people had given me and you can see that he’s gone from St Mark’s Square around the corner, over a bridge and then he took another photo, so it was great to follow his path.

Courtesy Dave Tomkins
Tomkins enjoys imagining his grandfather strolling around cities, camera in hand.

“The same thing happened in Hong Kong. I can imagine he went for a little stroll with his camera and I retraced the journey he went on which was pretty cool for me to do.”

To date, Tomkins has had more than 800 emails and in July this year, Photo 1 was identified as being taken in Espejo, Spain, leaving only one location to be found.

Courtesy Stephen Clarke
This last image is the only location yet to be identified.

He has suspicions that the last remaining image was taken in Switzerland but has bittersweet feelings about it being found.

“It’s really weird now there’s only one left to find. This is such a cool thing for me because I get to talk about grandpa and learn about him and tell people about him all the time. It almost feels like he’s still out there somewhere.

“If we find that last one, it’s almost like then it’s finished, there’s nothing more to keep talking about.”

Halima Ali is a London-based freelance journalist and editor. She tweets @Halima_Ali