Colorado Springs, Colorado
Colorado Springs is home to several important military installations.
One of the most significant is the North American Aerospace Defense Command (NORAD), which monitors and protects airspace over the United States and Canada.
Peterson Space Force Base is also located in the area and plays a role in space-based military operations.
The city has nearly 492,000 residents and acts as both a major population centre and a military hub.
However, the surrounding Rocky Mountains limit the number of evacuation routes, which could lead to heavy traffic and congestion during an emergency.
Omaha, Nebraska
Omaha plays a major role in the command structure of the US military.
Just outside the city is Offutt Air Force Base, which serves as the headquarters of the United States Strategic Command.
This command centre oversees the nation’s nuclear weapons and global military operations.
With about 486,000 residents, Omaha sits close to one of the most important command centres in the US defence system.
Severe winter weather and limited shelter infrastructure could make evacuation difficult during a crisis.