It's about four-fifths as long as Boniface VI's reign.
In other words, 300 hours is 0.830 times the length of Boniface VI's reign, and the length of Boniface VI's reign is 1.20 times that amount.(AD 896)
The Church's enigmatic, shortest-reigning Pope, Boniface VI was pontiff for a period of 360 hours 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-and-a-half times as long as The Apollo 11 Mission.
In other words, 300 hours is 1.536020 times the length of The Apollo 11 Mission, and the length of The Apollo 11 Mission is 0.6510330 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 195.310 hours. The total time spent by astronauts Neil Armstrong and Edwin "Buzz" Aldrin on the Moon's surface was 2.611110 hours.
It's about two-fifths as long as a William Henry Harrison's Presidency.
In other words, 300 hours is 0.39660 times the length of a William Henry Harrison's Presidency, and the length of a William Henry Harrison's Presidency is 2.5210 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 756.50 hours 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 two-and-a-half times as long as The Voyage of the Titanic.
In other words, 300 hours is 2.7190 times the length of The Voyage of the Titanic, and the length of The Voyage of the Titanic is 0.36780 times that amount.(a.k.a. RMS Titanic) (1912) (from Southampton, Hampshire, England to near the Grand Banks of Newfoundland)
110.30 hours into its maiden voyage, the RMS Titanic had completely sunk after colliding with an iceberg. The sinking was one of the deadliest maritime disasters in peacetime history, resulting in the deaths of 1,517 passengers and crew.
It's about one-fourth as long as The First US Continental Congress.
In other words, 300 hours is 0.250 times the length of The First US Continental Congress, and the length of The First US Continental Congress is 4 times that amount.(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 1,200 hours. 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 five times as long as The Great Chicago Fire.
In other words, the length of The Great Chicago Fire is 0.20 times 300 hours.(1871) (Chicago, Illinois)
The Great Chicago Fire started at about 9am and burned for 50 hours between October 8th and October 10th, 1871. Chicago had experienced twenty smaller fires in the 300 hours leading up to the blaze, due to drought conditions, strong winds, and the abundance of wooden buildings at the time.
It's about one-fifth as long as Columbus' voyage to America.
In other words, the length of Columbus' voyage to America is 5 times 300 hours.(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 — 2,000 hours 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.