Hundreds of people travelled between London Paddington and Exeter St Davids on the last scheduled InterCity 125 journey to the West country.
The sold-out trip was attended by hundreds of railway enthusiasts, including the train's designer, 89-year-old Sir Kenneth Grange.
He said for many commuters the train had become part of their life.
The 1970s icon is being replaced with the bullet-style electric InterCity Express Trains.
"All sorts of people have got to know this thing as part and parcel of their life, particularly those who had used it frequently for commuting," Sir Kenneth said.
"It's more familiar than their motor car."
The 18:30 from Paddington to Taunton had been extended to run to Exeter St Davids due to demand, and was reservation only.
It rolled into Exeter at 22:00 on Saturday.
All along the route, enthusiasts gathered to take photos and get a last look at the train.
The InterCity 125 engines are now destined to run in Scotland and local routes in Cardiff and Cornwall.
Others will be scrapped after nearly five decades of service.
On board: Jonathan Holmes, BBC News Online
As far as railway journeys go, this was certainly one of the more unusual trips I've taken.
The atmosphere was one of celebration as hundreds of railway enthusiasts turned out en masse to mark this occasion.
Alcohol was free-flowing in the buffet car, which was also doing a brisk trade in souvenirs such as window stickers and posters.
The designer of these iconic engines was on board. Sir Kenneth Grange told me that although it was a sad occasion, he was delighted his 1970s design had endured for so long.