Mick Aston, a former resident academic on Channel 4's Time Team, has died at the age of 66.
He appeared on the show, which sees experts carry out archaeological digs, from its inception in 1994 until 2011.
Professor Aston lived in Somerset and taught at a number of UK universities.
Time Team's official Twitter account tweeted: "It is with a very heavy heart that we've been informed that our dear colleague Mick Aston has passed away. Our thoughts are with his family."
The exact circumstances of the death of Prof Aston, who was born and raised in Oldbury, in the West Midlands, and was known on the show for his colourful jumpers and unruly white hair, are not yet known.
Close friend and former Time Team colleague Phil Harding said he had received the news from Prof Aston's son, James Aston.
Mr Harding, 62, said that although Prof Aston had suffered health problems, his death had come as a shock.
"It just seems so incredible, like a bad dream, but unfortunately this is no dream," he said.
The archaeologist said Prof Aston was a "unique man" who "everybody loved".
"He just had a way with people. I cannot believe there was anybody who disliked him, he just had such a relaxed way," he said
"He had incredible knowledge and an effortless way of making archaeology accessible to people."
Channel 4's head of factual programming, Ralph Lee, told the BBC: "We are terribly saddened to hear about the death of Professor Mick Aston.
"He was a brilliant communicator and his important contributions to Time Team over the years have played a key role in making archaeology so popular."
Francis Pryor, who also worked on Time Team, said Prof Aston had been a "remarkable archaeologist who could really dig".
Professor Pryor said: "I will remember him fondly - [he] was a warm, loving, nice man.
"He did very good work on original British towns... and he was an authority on monastic church archaeology and early medieval archaeology."
Prof Aston had appeared as the senior archaeologist in 19 series of the programme, in which specialists carry out an archaeological dig in the space of three days.
"In fact he was partly responsible for its creation after telling Tim Taylor, series producer, that it would be possible to evaluate a site in only three days," a biography on the Time Team website says.
It says he had worked in archaeology for more than 40 years, adding: "Mick had a childhood love of archaeology, despite his school's best attempts to dissuade him."
It adds that Prof Aston was a "passionate believer in communicating archaeology to the public".
Prof Aston studied geography with a subsidiary in archaeology at Birmingham University.
He joined the University of Bristol in 1979, organising and promoting lifelong learning and continuing education in archaeology.
From 1996 to 2004, he was professor of landscape archaeology at the university, later becoming an emeritus professor in the same subject.
The university says on its website that alongside Time Team, Prof Aston worked on a major research project that investigated the origins of the English village at Shapwick, Somerset, and researched monastic and landscape archaeology throughout Europe.
He was also an honorary visiting professor at Exeter, Durham and Worcester universities, and had published a number of books relating to archaeology.
In July 2012, he received a lifetime achievement award at the British Archaeological Awards, a showcase for the best in UK archaeology.
Mark Horton, professor in archaeology at the university, said at the time that Prof Aston had made "the past accessible to all".
In February 2012, Prof Aston, writing in the Western Daily Press, explained his decision to quit Time Team a year earlier, saying it was because Channel 4 had altered its format and the show had been "dumbed down".
"There is a lot less archaeological content and a lot more pratting about. I was the archaeological consultant but they decided to get rid of half the archaeological team, without consulting me," he wrote.
Time Team fan Lee Brady, who set up a tribute group on social-networking site Facebook, said: "The Time Team crew and Channel 4 should commission a 'one-off' special dig in memory of Mick.
"He loved Time Team and it would be very fitting that they could do one more dig at a location Mick would have loved."
In October last year Channel 4 announced that the 20th series of Time Team would be the show's last.
The final series aired earlier this year but a number of special episodes are planned for next year.