Lincoln have been promoted to the Championship for the first time in 65 years with five games to spare after a 2-1 win at Reading.
Jack Moylan's stoppage-time winner secured their second-tier return to mark an incredible rise by the Imps, who were in non-League just nine years ago.
Lincoln earned promotion to League Two in 2017, then to League One in 2019, and seven years later, they will be playing Championship football for the first time since 1961.
Under Michael Skubala, the runaway League One leaders are now unbeaten in 24 matches and sit 12 points above second-placed Cardiff.
Lincoln have become the first team in the EFL to earn promotion this season.
Their stoppage-time win at Reading means the Imps have now won 27 matches in League One this term, only taking more victories during an EFL campaign in 1975/76 (32) and 1951/52 (30).
Needing just one point to return to the second tier, the Imps made a bright start and went ahead in the fifth minute through Ryan One.
Reading levelled in the second minute of stoppage time from a Lewis Wing free-kick, but Moylan snatched the winner four minutes later.
City's 2,884 fans in the packed away end had plenty to cheer early on when One nodded home a Reeco Hackett-Fairchild free-kick, which home goalkeeper Joel Pereira should perhaps have saved.
Reading, unbeaten at home in their previous 10 matches, were unable to make any headway against the Imps' well-drilled defence.
Charlie Savage fired wastefully wide in a rare home attack, while defender Ryley Towler drove narrowly over as the visitors almost doubled their lead.
Lincoln were content to sit back for much of the second period, their job almost completed, as the Royals drove forward relentlessly but fruitlessly.
City substitute Alfie Lloyd headed wide from a Conor McGrandles cross before Reading equalised through Wing's fine 20-yard free-kick.
In the sixth minute of added time, Moylan slammed home from close range as Lincoln returned to the second tier for the first time since 1961 and dealt a blow to the home side's play-off hopes.
Lincoln boss Michael Skubala:
"We want to win the title, the lads have said that they definitely want to win it. It's going to be tough, but let's go and get that done as well.
"Every game is tough, but if we can go and put in some more good performances, we can do it.
"We'll enjoy tonight, we'll go out and have a beer. But we'll be back in on Wednesday, after a day off tomorrow, and then we'll be ready for a big game at home [Leyton Orient on Saturday].
"It's an unbelievable feeling now. The lads have been excellent all season and to get the job done today, to get promoted on Easter Monday, just epitomises our season.
"Every game is tough at this level. You have to be ready, you have to be on it, and Reading are good team and it was an excellent goal from Lewis Wing that brought them back into it.
"Be we kept believing, that we could catch them on the counter, and that's what happened.
"I'm not really thinking about next season yet. I'm not thinking about anything else today, I'm just enjoying this."
