In the coming days, UFC will celebrate it's 25th anniversary by hosting a card in Denver, the same city they held their inaugural event.
Originally from the basis of the "Gracie Challenge," the Ultimate Fighting Championship first began on November 12, 1993 featuring a single-night, eight-man tournament for the chance to win $50,000, as fighters from across multiple disciplines, across the world came down to the McNichols Sports Arena in Denver, Colorado.
Heading into their seventh event in the 'Mile High City,' we look at five memorable moments from UFC events in Denver.
Royce Gracie vs. Ken Shamrock - UFC 1
The original rivalry in the UFC began in their very first event when Royce Gracie and Ken Shamrock met in the semifinals of the UFC 1 tournament.
Royce was entering as the representative of the legendary Gracie family, and representing the family's traditional Brazilian Jiu Jitsu. Older brother Rickson was described as the most talented and stronger fighter, however to show the true technical skill of BJJ, Rorion, another brother in the Gracie family promoting the event, chose Royce to represent the family.
Shamrock entered the UFC as a former King of Pancrase, working with Japanese wrestling legends Masakatsu Funaki and Minoru Suzuki.
Gracie submitted one-gloved boxer Art Jimmerson, while Shamrock heel hooked Tae Kwon Do black belt Patrick Smith to meet in the semifinal.
The fight started with Gracie shooting a takedown on Shamrock, who defends with a sprawl. Shamrock attempts to reverse Gracie back into his guard, but Gracie defends and hits a switch to stand back up against the cage. Gracie gets some room in the clinch and attempts to pull guard on Shamrock. Shamrock decides to posture up and fall back for a leglock, which Gracie denies as he steps to take mount, but lands into half guard. As Shamrock tries to escape, Gracie sinks in the choke, to Shamrock tapping. After confusion from the referee, Gracie is declared the winner.
Gracie would go on to win in the finals to become UFC 1 tournament champion.
The two would face off again another two times in their career in their over 20-year rivalry fighting to a draw at UFC 5, and with Gracie winning controversially after a low blow at Bellator 149 in 2016.
Dan Severn vs. Tank Abbott - Ultimate Ultimate 1995
After UFC's first two events in Denver, they returned for their third at UFC's The Ultimate Ultimate on December 16, 1995.
The Ultimate Ultimate was the first UFC event not featuring stars Royce Gracie and Ken Shamrock, thus giving the opportunity for other fighters to step into the spotlight.
Dan Severn entered the Ultimate Ultimate 1995 tournament after winning the UFC 5 tournament and a loss challenging Shamrock for UFC Superfight Championship.
Tank Abbott was making his sophomore appearance for UFC after debuting at UFC 6 making it all the way to the tournament finals, losing to Oleg Taktarov.
Shamrock defeated Paul Varelans, while Abbott submitted UFC 3 tournament champion Steve Jennum to meet in the semifinal.
Severn would dominate Abbott on the ground, battering the street-brawler for majority of the fight to win a unanimous decision. Severn would then defeat Oleg Taktarov in the final to win the tournament.
Severn and Abbott would also both enter the professional wrestling industry at some time as well.
Jon Jones vs. Quinton "Rampage" Jackson - UFC 135
After The Ultimate Ultimate, it took the UFC nearly twenty years to return to Denver.
Jon Jones was scheduled to take on Rashad Evans a month prior at UFC 133, but withdrew from the fight due to a hand injury. Jones was reportedly to be out of action until late 2011, which Evans elected to take another bout. Later on Jones found out the injury was not as serious and would not sideline him as long, so he was set up to make his first title defense against Quinton "Rampage" Jackson in the 'Mile High City.'
Jones revealed to MMAFighting that heading into his fight against Rampage was the only time he has truly been 'intimidated.'
"He howls and the big old chain and everything. I kind of looked up to him and idolized him. Even though I knew I was a better martial artist, there was almost like a big-brother complex in there somewhere in a weird way. I used to have bad dreams of things not going my way against 'Rampage.'"
Jones dominated the fight against Rampage, controlling the distance with strikes and oblique kicks. Jones began opening up, taunting the out-matched Jackson in the third round.
Jones eventually took the fight to ground in the fourth round, submitting Jackson with a rear-naked choke, marking the only time Rampage has been finished in the Octagon.
Donald Cerrone vs. Melvin Guillard - UFC 150
Donald Cerrone may not be the only fighter on this list with a feud with his former Jackson-Wink MMA camp.
Following UFC 136, Melvin Guillard elected to leave the famed Albuquerque camp for the newly-formed Blackzilians team, along with Rashad Evans, who was having his own issues with the team (who in turn would have faced Jon Jones).
Since leaving the team, Guillard split a pair of bouts, while Cerrone was 2-1, only losing to Nate Diaz, setting up a showdown between the pair of former training partners in Cowboy's backyard.
It was reported that Cerrone was getting the better of Guillard during sparring sessions, while Guillard would apparently best Cerrone on the ground.
Throughout fight week, Guillard and Cerrone would be cordial. Both fighters would embrace during open workouts and other media obligations.
In the opening seconds, Guillard would drop Cerrone and swarm him with strikes. Cerrone would eventually regain his space and get back his composure.
A little after a minute, Cerrone would land a glancing head kick on Guillard to wobble him. Cowboy would follow up with a single punch to knock out his former training partner.
Valentina Shevchenko vs. Julianna Pena - UFC on FOX 23
The last main event for UFC's Denver event was between women's bantamweight contenders Valentina Shevchenko and Julianna Pena.
Shevchenko was coming off a close loss to current women's bantamweight champion Amanda Nunes in a non-title affair at UFC 196, then rebounded with a win over former champ Holly Holm.
At the time, Pena was undefeated in the UFC with her most recent win being over former title challenger Cat Zingano at UFC 200.
Heading into the fight, Shevchenko and Pena were ranked number-one and number-two in the division, with the winner to earn a title shot at Nunes.
In the first round, Pena would begin pressuring Shevchenko into clinches, throwing strikes during grappling exchanges. Shevchenko would catch Pena throwing a knee and take her down. Pena would threaten with an armbar from the bottom, but could not capitalize due to the round ending.
It was much of the same in the second round, with Pena controlling top position on Shevchenko during the grappling exchanges. With forty seconds to go, Shevchenko isolates one of Pena's arms and commits to an armbar, forcing Pena to tap.
Shevchenko would go on to earn another crack at Amanda Nunes, losing by close split decision in UFC 215.