Cruelest week in history: 13 tragedies (earthquake, Titanic, Columbine) happened around April 20

"It's been a week." You've heard that before, right? For some reason, the week of April 15-21 has been unusually cruel in history. One might call it "the cruelest week."

Historically, the week of April 15 is no stranger to tragedy. While disaster can strike at any time, an unusual amount of misfortune seems to take place on a few inauspicious days in April. Eerie coincidence? In most cases, yes. But it leads one to wonder if a day (or a week) can simply be unlucky.

Below is a list of 13 historic tragedies that happened during the week of April 15-21.

Lincoln Assassination: April 15, 1865

Shortly after the end of the American Civil War, President Abraham Lincoln was shot in the head by John Wilkes Booth while attending a play at Ford's Theater in Washington, D.C.

Lincoln was carried to a house across the street from the theater, where he died.

Booth escaped the theater after the assassination, but was shot to death 11 days later when the 16th New York Cavalry attempted to capture him on a farm in Virginia.

Presidents Day: George Washington (sort of) has 2 birthdays. Why isn't it Florida holiday?

San Francisco Earthquake: April 18, 1906

Early in the morning of April 18, 1906, a powerful earthquake, centered on the northern California coast, shook the city of San Francisco.

After the quake, a fire broke out in the city and burned for four days and nights. Between 700 and 3,000 people were killed and over 80% of the city was destroyed. Up to 300,000 people were left homeless.

In an eerie coincidence, on June 15, 2006, a century after the massive San Francisco Earthquake, there was another natural disaster in San Francisco. According to CNN, "A magnitude 4.7 earthquake and multiple aftershocks shook the south San Francisco Bay Area. The effects were felt in a 28-mile radius. The earthquake, which the U.S. Geological Survey deemed 'light,' happened at 5:24 a.m. PT." No one was hurt, and there was no significant damage reported.

Sinking of the Titanic: April 15, 1912

The passenger liner RMS Titanic sank after striking an iceberg on her maiden voyage across the Atlantic.

The ship carried only 20 lifeboats, which provided an escape for just a fraction of the estimated 2,224 passengers and crew. More than 1,500 people died in the disaster, making it one of the worst commercial maritime disasters during peacetime.

Ludlow Massacre: April 20, 1914

Striking coal miners and their families were staying in a tent colony outside Ludlow, Colorado, when an ongoing conflict with the Colorado Fuel and Iron Co. and the Colorado National Guard turned deadly.

When a gunfight broke out between the miners and guards, the guards fired on the tent colony with a machine gun. 20 people, including 12 children, were killed.

Hillsborough Disaster: April 15, 1989

Overcrowding in the standing-only central pen at Hillsborough Stadium in Sheffield, England, led to a disastrous event in which 96 people were crushed to death and 766 were injured.

The central pen became dangerously crowded during an Football Association Challenge Cup semi-final match, when police failed to control the number of people coming into the area. People at the back of the pen were not aware that people near the front were being crushed as more and more fans streamed in.

Police and bystanders didn't fully realize what was happening until a near-goal caused fans in the pen to surge forward, breaking a barrier and spilling injured people onto the field.

The Hillsborough Disaster remains the UK's deadliest sporting disaster.

Waco Siege ends: April 19, 1993

The Waco Siege began when members of the Bureau of Alcohol, Tobacco and Firearms attempted to raid a compound occupied by heavily-armed members of the Branch Davidian religious group.

The resulting conflict lasted several weeks and involved the ATF, the FBI, law enforcement and the US military.

At the end of the standoff, the FBI used tear gas in an attempt to flush the Branch Davidians out of the compound. Shortly after, a massive fire broke out, which resulted in the deaths of 76 people, including children.

Oklahoma City Bombing: April 19, 1995

A truck loaded with ammonium nitrate fertilizer exploded outside the Alfred P. Murrah federal building in downtown Oklahoma City, killing 168 people. The blast was, at the time, the worst terror attack in United States history.

Timothy McVeigh and several co-conspirators orchestrated the attack, which McVeigh said was in retaliation to the government's handling of the siege at Waco.

McVeigh was convicted and executed by lethal injection in 2001.

Oklahoma City bombing: The attack, the aftermath and a city's resilience

Columbine High School Massacre: April 20, 1999

Two students at Columbine High School in Littleton, Colorado, shot and killed 12 students and one teacher and wounded an additional 21 people in a massacre that made the word "Columbine" synonymous with school shootings.

Eric Harris and Dylan Klebold initially planned a bomb attack, but the propane bombs they planted in the school cafeteria failed to detonate.

Harris and Klebold died by suicide after exchanging gunfire with police.

Virginia Tech Shooting: April 16, 2007

Undergraduate student Seung-Hui Cho shot 49 people, killing 32, in one of the worst school shootings in United States history.

Cho shot and killed two students in a residence hall before returning to his room, changing out of his bloodstained clothes and heading to the engineering, science and mechanics building. There, he killed 30 more people before fatally shooting himself.

Deepwater Horizon Disaster: April 20, 2010

The Deepwater Horizon oil drilling rig was destroyed by an explosion and subsequent fire while drilling for BP about 40 miles off the Louisiana coast. 11 workers were killed and 17 others were injured.

Following the explosion, engineers discovered a massive oil leak was spreading from the well at the bottom of the Gulf of Mexico. The well continued to leak for weeks, as several containment efforts were unsuccessful. The spill caused massive ecological damage in the Gulf of Mexico and along the Gulf Coast.

Boston Marathon Bombing: April 15, 2013

Terrorists detonated two bombs near the finish line at the Boston Marathon in 2013, killing three people and injuring more than 250.

Two brothers, Dzhokhar and Tamerlan Tsarnaev were identified as suspects. The brothers engaged police in a dramatic chase and shootout that left Tamerlan Tsarnaev and a Massachusetts Institute of Technology police officer dead, and 17 other police officers wounded.

After his arrest, Dzhokhar Tsarnaev said the brothers were influenced by extremist Islamist beliefs.

West Fertilizer Co. Explosion: April 17, 2013

A fire broke out at a fertilizer storage and distribution facility in the city of West, Texas, about 18 miles north of Waco. As firefighters responded, a massive ammonium nitrate explosion killed 15 people, injured 160 others and destroyed or damaged more than 150 buildings in West.

The blast was the equivalent of more than 7 tons of TNT and created a 93-foot wide crater. Windows were blown out of buildings miles away, and the explosion shook the ground with the strength of a magnitude 2.1 earthquake.

In 2016, the ATF said their investigation revealed the fire had been intentionally set.

Notre Dame Cathedral Fire: April 15, 2019

A fire started in the roof of the famous Notre-Dame de Paris cathedral and spread through the structure, toppling the iconic lead and timber spire as firefighters rushed to save the irreplaceable relics and works of art from the 800-year-old church.

When the fire was finally extinguished, the cathedral's roof was almost completely burned and the structure had suffered major damage. The facade, with its distinctive towers, remained standing, though the priceless rosette window had fallen away.

The landmark cathedral was undergoing a $6.8 million renovation when the fire broke out.

Contributing: Associated Press

This article originally appeared on Florida Today: Titanic, Notre Dame, Columbine: Week of April 20 no stranger to tragedy