Erik Sass has been covering the events of World War I exactly 100 years later in the WWI Centennial series. To commemorate Veterans Day – originally known as Armistice Day, marking the end of hostilities on November 11, 1918 – here are eleven photos highlighting different aspects of the war. 

 A composite photo by Frank Hurley depicts warplanes in close support of British soldiers going "over the top."

Crewmembers make a last-minute escape from a merchant ship sinking after being torpedoed by a German U-boat. Note some men still descending the sides of the ship; around 20,000 British, Allied, and neutral merchant crewmen and civilians lost their lives in U-boat sinkings. 

A rare color photograph of British stretcher-bearers carrying a wounded comrade through the mud in Flanders.

An Australian soldier carries a wounded comrade at Gallipoli.

 

Spent shell casings after a British artillery bombardment in Greece.

A German infantry attack at Verdun on March 15, 1916. Several soldiers are using grenades and one is equipped with a flamethrower.

A French soldier is shot during a counterattack at Verdun.

Another rare color photo showing the Flanders countryside after the Battle of Passchendaele (Third Ypres) in 1917. 

A German messenger dog leaps over a trench. Millions of animals served in the war, including horses, dogs, and carrier pigeons.

A crater left by a British mine detonated on July 1, 1916, on the first day of the Battle of the Somme. The 27 tons of high explosive left a crater 40 meters deep with a circumference of 300 meters. 

The basement of the house in Yekaterinburg, Russia, where Tsar Nicholas II and the rest of the Russian royal family were shot by their Bolshevik captors on July 17, 1918.