The Double has been a rather common occurrence in the past decade - indeed, Arsenal have managed it twice under Arsène Wenger. But go back to pre-Premiership days and you'll discover that winning the league and FA Cup in the same season was truly the holy grail of English football.
When the 1970/71 campaign kicked off, Tottenham stood alone as the 20th century's sole Double winners. By the end of that season, Bertie Mee's Arsenal emulated what Bill Nicholson's Spurs did 10 years earlier.
The Gunners clinched the first leg of their historic achievement at the home of their old rivals, claiming the league title with a 1-0 win at White Hart Lane. Five days later, Mee's men headed for Wembley with Liverpool standing between them and a feat which would secure their places in history.
On a baking hot day at Wembley after a long, hard season, both teams found it hard going. Arsenal carved out the better chances but their finishing touch deserted them in normal time as Ray Kennedy, George Graham and Charlie George failed to convert decent opportunities.
And so to extra time. The Double was still on but, with just two minutes played, it was Steve Heighway and Liverpool who struck the first blow. Bob Wilson anticipated a cross but the Liverpool winger slammed the ball in at the keeper's near post.
Not for the first time, Arsenal would have to dig deep for victory. It was Frank McLintock, on the verge of a fifth successive Wembley defeat, who rallied his team-mates. And within minutes they were level thanks to Eddie Kelly's toe-poke. The equaliser was claimed by Graham but television pictures suggested that the midfielder had not touched the ball on its way past Ray Clemence.
Either way Arsenal were back on track and there was even better to come. George collected a pass from John Radford and hammered a shot past Clemence from 20 yards. As the ball hit the back of Liverpool's net, George sank to the Wembley turf and lay on his back with his arms outstretched. His celebration remains one of the FA Cup's most iconic images.