Put simply, it is the record for the furthest distance ridden in a velodrome in one hour and has been held by some of the most revered athletes in the history of the sport. Fausto Coppi, Eddy Merckx and Miguel Indurain have all held this record at one time or another, with Merckx having described his successful attempt in 1972 as "the hardest ride I have ever done".
In decades gone by, breaking the hour record was valued almost as highly as winning some of the great races but, since the turn of the century, interest has fizzled out. Barely a thought was given by any of today's riders to a serious assault on the current mark. The subject occasionally popped up in the conversation of current riders, but few serious bids to break the record ultimately came to fruition.
The reason for this is simple. In 2000, the sport's governing body, the International Cycling Union (UCI), ruled that all record attempts must be made on equipment as similar as possible to that used by Merckx for his 1972 record, in which he rode 49.431km. This feat is called 'The Athlete's Hour'. The consequence of this ruling 14 years ago was that all records which had been set on bikes outwith these regulations were to be disregarded and the technical innovations which had moved the sport on so significantly could not be capitalised upon.
When Graeme Obree set his famous hour record on 'Old Faithful' in 1993, he covered 51.596km, only for his record to be broken by 0.7km just six days later by his great rival, Chris Boardman. The Englishman would eventually set a mark of 56.375km in 1996 but, as all of these distances were accomplished using the popularised 'Superman' position, they were removed from the record books in 2000 following the UCI's revision of the rules. The current record stands at 49.70km, set by the Czech rider, Ondrej Sosenka, in 2005.
The UCI have made an intriguing announcement this month, though. They have jettisoned their own rule which states that equipment must be similar to that of Merckx and have, in one fell swoop, renewed the interest in the hour record.
Riders can now make full use of modern technology, with any bike which complies with rules for endurance track competition being permitted for future attempts. This move by the governing body is logical, if somewhat belated.
In revamping the rules, the UCI hope to lure some big-name riders into making an attempt to break Sosenka's current record, and it has had the desired effect almost immediately. Sir Bradley Wiggins had expressed a fleeting interest in attempting to break the record in previous years but no real action was forthcoming.
However, already the 2012 Tour de France champion has voiced his desire to go for the record under the new rules and this time his pronouncements appear far more convincing. The hour record is a feasible goal for Wiggins, who is unlikely to be given the opportunity to regain his yellow jersey in the coming years, or at least not while his compatriot and Sky team-mate Chris Froome is on the scene.
So, for Wiggins, a rider who is unambiguously motivated by goals and is also a keen student of the history of the sport, an attempt on the hour record could be an astute and realistic target for this season. An Olympic gold medallist on the track and a time-trial specialist on the road, the smart money would be on the Englishman to improve on Sosenka's mark.
The names of the other usual suspects have, unsurprisingly, been touted, with the triple world time-trial champion Tony Martin and time-trial specialist Taylor Phinney among the most likely to mount an attack on the record.
Perhaps the most intriguing noises have come from closer to home. Obree told Cycling Weekly that he was "tempted" to have a fresh crack at the record, declaring that the current mark of 49.70km was "really low-hanging fruit on a modern aero bike".
That Obree's interest has been piqued should come as little surprise to even casual observers. Just last year he made an attempt on the human-powered land speed record, and his motivation to set records has remained undiminished since his professional cycling days. On describing his previous attempts at the hour record, Obree said: "The pain is so bad; it's like pulling your fingernails out one by one. You just have to think about your rhythm because all that's left at the end is your subconscious." Yet, for all the suffering one must go through to break the hour record, Obree is exactly the type of character who can endure that pain.
Irrespective of whether it is Obree or another rider, the hour record will be broken sooner rather than later. In resetting the rules, the UCI have reignited the riders' interest in this most historic of records and the resumption of serious attempts will be a fascinating addition to the cycling calendar.