It's about twenty times as long as Columbus' voyage to America
In other words, the length of Columbus' voyage to America is 0.05 times 3 years.(1492) (first voyage)
Attempting to find a western route to Asia, Christopher Columbus set sail on August 3rd, 1492 and landed in the Bahamas on October 12th — 0.20 years later. After one of Columbus' ships, the Santa Maria ran aground in present-day Haiti, he ordered that the timber be used to used to build a fort and settlement called La Navidad; it remains missing to archaeologists to this day.
It's about twenty times as long as The First US Continental Congress
In other words, the length of The First US Continental Congress is 0.045 times 3 years.(1774) (Philadelphia, Pennsylvania)
The First Continental Congress — which included such notable members as Samuel Adams, Thomas Paine, Patrick Henry, John Jay and George Washington — met from September 5th to October 26th, 1774 — a total of 0.140 years. Of the thirteen original American colonies in existence at the time, only the Province of Georgia sent no delegates to the Congress.
It's about one-thirty-fifth as long as Pepi II's reign
In other words, the length of Pepi II's reign is 30 times 3 years.(a.k.a. Neferkare) (2278 BCE - 2184 BCE)
The sixth dynasty pharaoh of Egypt's Old Kingdom, Pepi II Neferkare ascended to the throne at the age of six and is generally thought to have reigned until his death at the age of one-hundred — a total of 94 years. His reign was the longest of any monarch in history.
It's about thirty times as long as a William Henry Harrison's Presidency
In other words, 3 years is 34.770 times the length of a William Henry Harrison's Presidency, and the length of a William Henry Harrison's Presidency is 0.02876 times that amount.(a.k.a. William Henry Harrison, a.k.a. "Tippecanoe," a.k.a. "Old Tippecanoe") (1841)
Having caught pneumonia and pleurisy early in his term as President of the United States, William Henry Harrison died after 0.0863 years minutes in office. Following his death, Congress approved a Presidential widow's pension for Harrison's wife, Anna Symmes, who received a year's worth of Harrison's presidential salary — $25,000 — and the right to free postage for the remainder of her life.
It's about 75 times as long as Boniface VI's reign
In other words, the length of Boniface VI's reign is 0.014 times 3 years.(AD 896)
The Church's enigmatic, shortest-reigning Pope, Boniface VI was pontiff for a period of 0.041 years in AD 896 before dying under somewhat mysterious circumstances. His election was subsequently pronounced null by Pope John IX because Boniface had been previously defrocked while serving as a Roman priest.
It's about one-eighty-fifth as long as a Giant Tortoise's Lifespan
In other words, the length of a Giant Tortoise's Lifespan is 83 times 3 years.(for Adwaita, an Aldabra Giant Tortoise) (Dipsochelys dussumieri, formerly Geochelone gigantea)
Adwaita, an Aldabra Giant Tortoise who lived the later part of his life in the Alipore Zoological Gardens in Kolkata, India, was 250 years old at the time of his death. Once a pet of Major-General Robert Clive, 1st Baron Clive, who is credited with securing India as a colony of Great Britain, Adwaita lived through the entirety of India's 190 years as a British colony.
It's about 150 times as long as The Apollo 11 Mission
In other words, 3 years is 134.6480 times the length of The Apollo 11 Mission, and the length of The Apollo 11 Mission is 0.00742677 times that amount.(1969) (total mission length)
The first trip by humans to the surface of the Moon, the Apollo 11 Mission began with the launch of the spacecraft from the Kennedy Space Center in Florida on July 16th, 1969 and concluded with the return of the command module on July 24th, 1969 — a total mission time of 0.0222804 years. The total time spent by astronauts Neil Armstrong and Edwin "Buzz" Aldrin on the Moon's surface was 0.000297868 years.