Four units will deploy across the world in the coming months, the Army announced on Wednesday.

Three of the four will deploy in the spring, while the fourth unit will deploy in the summer.

The deploying units, which include two armored brigade combat teams of about 4,500 soldiers each, are:

10th Mountain Division headquarters

The 10th Mountain Division headquarters from Fort Drum, New York, will deploy to Iraq in the spring, according to a news release.

These soldiers will replace the 1st Armored Division headquarters, of Fort Bliss, Texas, as part of a regular rotation to support Operation Inherent Resolve.

Personnel with the 10th Mountain Division headquarters have completed multiple training events, including a warfighter exercise, to prepare for the deployment.

“We are honored to be part of the global coalition in support of the Iraqi Security Forces as they consolidate gains from their successful efforts to achieve a lasting defeat of ISIS in Iraq,” Maj. Gen. Walter Piatt, the 10th Mountain commander, said in the release. “We will build upon the success of the 1st Armored Division as we look forward to partnering with the coalition forces and the Iraqi Security Forces as they build long term stability through credible and ready security forces.”

101st Airborne Division headquarters

The 101st Airborne Division headquarters from Fort Campbell, Kentucky, will deploy to Afghanistan this spring, the release said.

It will replace the 3rd Infantry Division headquarters, of Fort Stewart, Georgia, as part of a regular rotation to support Operation Freedom’s Sentinel.

“The 101st Airborne Division remains, as it did 75 years ago when it was forged during the maelstrom of World War II, ready to answer the call to fight and win our nation’s wars,” Maj. Gen. Andrew Poppas, the 101st Airborne commander, said in the release. “This will be the division headquarters’ fourth deployment to Afghanistan in the last decade. We know the terrain, we know our partners and we know our mission.”

1st ABCT, 3rd Infantry Division

The 1st Armored Brigade Combat Team, 3rd Infantry Division from Fort Stewart will deploy in the spring to South Korea.

The brigade will replace the 2nd Armored Brigade Combat Team, 1st Cavalry Division, of Fort Hood, Texas, as part of a regular rotation to support the United States’ commitment to its Republic of Korea partners, the release said.

“The Raider Brigade has a proud history of answering the nation’s call,” Col. Mike Adams, the 1st ABCT commander, said in the release. “Our unit recently completed a rigorous training cycle that culminated with a decisive action training environment rotation to the National Training Center at Fort Irwin, California. We are trained and ready to perform our mission as part of a long-standing alliance between the Republic of Korea and the United States.”

This deployment also marks the return of the 3rd ID to Korea, the release said. The division supported the Eighth Army’s combat missions until 1953.

1st ABCT, 1st Cavalry Division

The 1st Armored Brigade Combat Team, 1st Cavalry Division from Fort Hood will deploy to Europe this summer.

The ABCT will replace the 2nd Armored Brigade Combat Team, 1st Infantry Division, of Fort Riley, Kansas, as part of a regular rotation to support Operation Atlantic Resolve.

“The Ironhorse Brigade looks forward to returning to Europe to continue working with our NATO and regional partners,” Col. Wilson Rutherford IV, the 1st ABCT commander, said in the release. “We are a trained armored brigade combat team which is fully prepared to conduct a full range of operations in support of U.S. Army Europe. Our professional leaders and soldiers are honored at the opportunity to contribute to this longstanding strategic alliance.”