F1 legend Ayrton Senna was killed in a crash at the San Marino Grand Prix on May 1, 1994, leaving the sport devastated.
Senna, regarded by many as the greatest F1 driver in history died when he smashed his Williams car at 305km/h into a concrete wall on the Imola track.
The three-times world champion was well known for his aggressive driving style and once said: "Winning is like a drug".
The Brazilian driver was a global superstar who was much loved all across South America.
Mystery still surrounds Senna's fatal crash but Williams team boss Frank Williams was cleared of manslaughter charges in 1997.
On May 1, 1999, the body of legendary British mountain climber George Mallory, who disappeared on Mount Everest in 1924, was discovered on the famous mountain.
His frozen corpse was found close to the summit, raising the possibility he may have climbed to the top almost 30 years before the successful ascent by New Zealander Sir Edmund Hillary and Sherpa Tenzing Norga.
The case of near identical US prison inmates Will West and William West and flaws in the recording of prisoners came to light on May 1, 1930.
When Will West arrived at Leavenworth prison, the police were told that he was already in prison, serving a life sentence for first-degree murder. He was checked on their files which matched his face with another William West in their database.
But after protests by Will West, they double checked their record and discovered the prisoners were completely identical but unrelated. The case highlighted to US authorities the need to adopt fingerprinting.
Miners Brant Webb and Todd Russell were found alive on April 30, 2006, after a mine collapse in Beaconsfield, Tasmania.
The pair were discovered alive in a telemover cage after they were heard yelling, five days after a rockfall triggered the collapse.
Doctors found them to be well, with only minor injuries.
Russell and Webb were finally freed on May 9 after a rescue tunnel was drilled to reach them.
They walked from the mine shaft lift at with arms raised after spending 321 hours trapped underground.
Fellow miner Lesley Knight was killed during the disaster.
An inquest into his death revealed that the mine was under financial pressure and sent workers down to levels previously closed off after an earlier large rockfall.
Tennis great Monica Seles was stabbed in the back while playing on court at a tournament in Hamburg, Germany on April 30, 1993.
The attack by a deranged fan of her rival Steffi Graf sent shockwaves around the world.
The injuries, while bad, were not as serious as they could have been.
Had the knife gone in a centimetre to the left, Seles would likely have been paralysed for life, if not worse.
On April 30, 1993, four years after releasing a plan for "an idea of linked information systems," computer scientist Tim Berners-Lee released the source code for the world's first web browser and editor.
The browser that he called WorldWideWeb became the first easy-to-use, royalty-free method of browsing the information network that became the internet the world knows today.
With Russian troops advancing into central Berlin, German fuehrer Adolf Hitler committed suicide on April 30, 1945, in his underground bunker.
While there has been speculation for decades about the manner of his death, it is widely believed that he shot himself.
Eva Braun, whom he had recently married, also took her own life.
Russian scientists confirmed on April 30, 2008, two skeletal remains found at Yekaterinburg in the Ural mountains were the the remains of Alexei and Anastasia, pictured, two of the children of the last Tsar of Russia.
They were among the entire royal family executed by the Bolsheviks in 1918.
Massive riots broke out in Los Angeles on April 29, 1992, when a jury acquitted four white police officers on charges of excessive force in the beating of black man Rodney King.
The decision, made by an all-white jury, caused a political outcry, and provoked fury in the largely black suburbs of south-central Los Angeles.
The riots lasted several days before police and the National Guard regained order. The violence left 55 people dead and thousands injured.
The origins of the LA riots in 1992 stem from image video shot the previous year by George Holliday that showed police officers beating King after a traffic stop in the city.
The tape was on television networks across the world a day later, and became a focus for accusations of racist brutality against the Los Angeles Police Department.
Rodney King later won $US3.8m damages from the City of Los Angeles.
The first international telephone call from Australia was made on April 29, 1930, when Prime Minister James Henry Scullin spoke with his UK counterpart for 15 minutes.
It was the result of experiments carried on for many months between the engineers from the post offices of both countries and work by the Amalgamated Wireless Company of Australia.
The United States began a chaotic evacuation of its citizens from Saigon on April 29, 1975, in response to advancing North Vietnamese forces.
It brought an end to US involvement in the Vietnam War that cost the lives of more than 58,000 American troops.
On April 29, 1993, Britain's Queen Elizabeth II announced the public would be allowed inside her London residence Buckingham Palace for the first time.
Money raised from entry fees would help pay for much of the $80 million cost of restoring Windsor Castle, damaged by fire the previous year.
On April 29, 2018, after 29 seasons and 636 episodes, animated series The Simpsons set a new record for the most primetime episodes in television history.
The Simpsons surpassed the previous record held by the popular western series Gunsmoke.
The Port Arthur massacre - Australia's deadliest mass shooting - took place on April 28, 1996.
The shooting rampage by gunman Martin Bryant at the historic site in remote Tasmania left 35 people dead and 18 wounded.
Police later established that Bryant, wielding a semi-automatic rifle, systematically hunted down down victims as he moved through the cafe, gift shop, carpark and elsewhere around the site.
Bryant later took a hostage and drove to a local guesthouse where earlier in the day he shot its two owners. Surrounded by police, he surrendered after an 18-hour siege.
Bryant was later jailed for multiple life sentences.
In the aftermath of the mass shooting, then Prime Minister John Howard introduced tough new gun laws banning semi-automatic and automatic weapons.
At the height of the Vietnam War, American world heavyweight boxing champion Muhammad Ali refused to be inducted into the US military on April 28, 1967, citing religious reasons.
His stand resulted in boxing officials stripping the flamboyant fighter of his world titles. Later in the year he was convicted in a US federal court of draft evasion.
On April 28, 1994, senior CIA officer Aldrich Ames and his wife Rosario pleaded guilty to spying for Soviet Russia.
Multiple US spies embedded in Russia's military and intelligence hierarchies were arrested and executed as a result of Ames' betrayal of them to his Russian spymasters.
Ames who was sentenced to life in prison for treason was paid millions of dollars by Russia for turning double agent.
Shrek the sheep from Tarras, Central Otago, New Zealand, was finally shorn live on TV after six years avoidance on April 28, 2004.
The fleece of wool weighed a whopping 27kg.