Paul Drinkwater, 52, carried out the attacks including one at knifepoint in Berkhamsted, Hertfordshire, in November and December 1984.
Drinkwater, of Berkshire, was jailed for 29 years after being found guilty of two rapes, indecent assault and robbery at St Albans Crown Court.
Judge Marie Catterson told him "these were horrific and dreadful crimes".
She said the attacks "had a profound and continuing harmful effect" on his victims.
The former landscape gardener and driveway layer was convicted of the rape and robbery of a 15-year-old girl in Durrants Lane on 25 November. He wore a mask and was carrying a knife.
He also raped an 18-year-old woman and indecently assaulting another woman aged 18 on 16 December in Bullbeggers Lane.
Prosecutor Ann Evans said on 14 January 2014 a DNA profile from Drinkwater, from Maidenhead, was provided to a forensic scientist.
A swab from the 15-year-old victim was matched as "seven million more times likely to come from Paul Drinkwater, rather than a person unrelated to him," she said.
Samples taken from the trousers worn by the 18-year-old rape victim matched Drinkwater.
In a victim impact statement read to the court, the woman attacked aged 15, said: "I still have a frightening image of the mask and his eyes."
Following the sentencing, one of the victims, now in her late 40s, told the court: "I feel like I have finally been let out of prison today.  I can get my life back."
A man who raped and sexually abused three teenagers more than 30 years ago has been jailed.