FORT BENNING, Ga. -- Many installations across the Army are marking or have marked the centennial of the construction of their posts, which occurred in the weeks and months following the U.S. declaration of war on Germany, April 6, 1917.

Fort Benning was one of the last installations to be activated in October 1918, just a month before the armistice was declared on Nov. 11, 1918.

To mark the occasion, the WWI history on display at the museum here has devoted a large exhibit to what is referred to as "the Great War."

David S. Hanselman, director of the Maneuver Center of Excellence's Museum Division, provided a tour.

The war effort was monumental, he said. Prior to World War I, the active and reserve components numbered only about half a million. By war's end, the combined total had grown to over four million.

The Selective Service Act of 1917 required all males aged 21 to 30 to register for military service. The act was amended in August 1918 to expand that age range to 18 to 45. More than half of those who served during the war were drafted and the rest volunteered.

The Army preferred that Soldiers volunteer. To support the recruitment effort, a number of colorful and creative recruiting posters were produced.

One poster promised free "food, clothing, living quarters, medical attention, dental attention, baseball, football and movies-theatre; plus $30 per month." No mention was made of combat hardships.

Another poster proclaimed: "There's the world before you, young man. Do you want to see it, earn a trade and live a strong, healthy life? If so, enlist and be happy -- you can't beat this!"

Another poster was designed to entice Soldiers already in the Army to re-enlist. It reads in part: "The Army is a big workman's school and you can learn any trade you desire -- from shoemaker to aviator mechanician -- and you earn while you learn."

Many who joined the Army ended up fighting the Germans on the Western Front in France and Belgium. A large painting depicts a scene from the front titled "The Menin Road," by Paul Nash.

The description below the painting states: "Many artists tried to capture the utter desolation, wreckage, mud and hopelessness of 'no man's land,' that horrifying place of death and fear between opposing forces on a World War I battlefield."

A life-size mockup shows Soldiers climbing a ladder out of their trench, preparing to charge enemy positions. Sometimes periscopes were used to look out over the parapet to see if the coast was clear to attack. If so, a whistle would have been sounded to signal climbing the ladder and crossing no-man's land toward the enemy, Hanselman said.

Also on display is a German MG08 machine gun that fires 450 rounds per minute -- it might have been used against U.S. Soldiers.

Enemy forces might also have chosen to launch a gas attack against Americans, if the wind was blowing in the right direction. Gas masks on display were used to protect the troops.

Some Soldiers also wore steel helmets for further protection. One of these is depicted at the museum, having been worn by an African-American Soldier from the famed 92nd Division Buffalo Division.

Although not widely adopted, experimental steel body armor was produced, resembling armor that knights might have worn. It too is on display.

U.S. Soldiers fought back with a large variety of weapons on display here, including an Mle 1914 Hotchkiss machine gun, made by the French, as well as a number of bolt-action rifles.

Americans sometimes attacked in tanks, such as the M-1917 light tank with 37mm cannon, also on display. Hanselman said it was restored by professional museum staff of the National Armor and Cavalry Museum.

Many other exhibits are featured including a life-sized mannequin depicting an Army nurse, first aid gear, radios and even a mockup of a homing pigeon being launched from a tank to carry a message back to headquarters.

The museum is quite large and the World War I exhibits alone would take the better part of a day to see. Other wars from the American Revolution to the current wars in Iraq and Afghanistan are also well represented.

Outside the museum is a full-size replica of the Vietnam Veterans Memorial Wall, as well as larger-than-life-sized depictions of U.S. Soldiers in combat gear from the last 17 years of warfare. The display is known as the "Global War on Terror Memorial."

On display behind the museum is a narrow-gauge locomotive and passenger car that once carried Soldiers to the frontlines.

Hanselman noted that the museum has been voted the best free museum in the nation by USA Today newspaper and one of the top 12 best military museums in the world by a CNN poll.

"We're pretty proud of that," he said.