A cyclist is offering £500 if anyone can help him find his modified black Trek Roscoe 7, with blue highlights on the pedals and grips, which was stolen from Mereworth Woods in Kent on Tuesday.
"It was stolen from right behind me while I stopped to clear a path,” Alastair Field told Kent Online.
“This guy, who had been watching me, hidden in a group of other people jumped out and rode away with it.
"He was acting alone, the others didn't know who he was so they were shouting to get my attention.
"I was in a state of disbelief for a while. I phoned the police straight away and I was very emotional and I'm really gutted it's gone."
The bike has great sentimental value to Field.
"I bought it brand new for a trek all the way to Bosnia,” he said. “After that I've taken it on various trips to the mountains in Germany, Belgium, and across Scotland. All of my free time is spent taking this bike on adventures.
"I've heavily modified it. It's now got blue highlights all over and it's very scratched and scuffed. The paint work has been worn away by all of the bags that I've had strapped to it.
"It has very wide tyres, and nearly all parts have been replaced from the factory stock, making it very unique and distinctive.
"It won't sell for very much money but I'm worried that because it has nice parts, they will be taken off and the frame will be thrown away when really it's the frame that means the most to me.
"It will take me years to properly build up another expedition bicycle so I'm really hoping I can get it back."
Anyone with information should call Kent Police on 01622 604100, quoting reference 5-1078.