Civil War reenactors portraying Union troops cross a bridge assembled across the Rappahannock River by Virginia Guard Soldiers from the Bowling Green-based 189th Engineer Company, 276th Engineer Battalion Dec. 8, 2012, during the observation of the 150th Anniversary of the Battle of Fredericksburg. The event commemorates the first amphibious assault undertaken while under fire in U.S. history when engineers from the Union Army built a pontoon bridge while under fire from Confederate Soldiers. Confederate and Union troops exchanged fire from their respective river banks as Union troops sailed across the river in pontoon boats before the majority of their forces crossed the bridge on foot. After crossing the bridge and clamoring up the banks of the Rappahannock, Union troops continued to engage Confederate forces in the streets of Fredericksburg, just as they did during the original battle 150 years ago. (Photo by Cotton Puryear, Virginia National Guard Public Affairs)Civil War reenactors portraying Union troops cross a bridge assembled across the Rappahannock River by Virginia Guard Soldiers from the Bowling Green-based 189th Engineer Company, 276th Engineer Battalion Dec. 8, 2012, during the observation of the 150th Anniversary of the Battle of Fredericksburg. The event commemorates the first amphibious assault undertaken while under fire in U.S. history when engineers from the Union Army built a pontoon bridge while under fire from Confederate Soldiers. Confederate and Union troops exchanged fire from their respective river banks as Union troops sailed across the river in pontoon boats before the majority of their forces crossed the bridge on foot. After crossing the bridge and clamoring up the banks of the Rappahannock, Union troops continued to engage Confederate forces in the streets of Fredericksburg, just as they did during the original battle 150 years ago. (Photo by Cotton Puryear, Virginia National Guard Public Affairs)Civil War reenactors portraying Union troops cross a bridge assembled across the Rappahannock River by Virginia Guard Soldiers from the Bowling Green-based 189th Engineer Company, 276th Engineer Battalion Dec. 8, 2012, during the observation of the 150th Anniversary of the Battle of Fredericksburg. The event commemorates the first amphibious assault undertaken while under fire in U.S. history when engineers from the Union Army built a pontoon bridge while under fire from Confederate Soldiers. Confederate and Union troops exchanged fire from their respective river banks as Union troops sailed across the river in pontoon boats before the majority of their forces crossed the bridge on foot. After crossing the bridge and clamoring up the banks of the Rappahannock, Union troops continued to engage Confederate forces in the streets of Fredericksburg, just as they did during the original battle 150 years ago. (Photo by Cotton Puryear, Virginia National Guard Public Affairs)Civil War reenactors portraying Union troops cross a bridge assembled across the Rappahannock River by Virginia Guard Soldiers from the Bowling Green-based 189th Engineer Company, 276th Engineer Battalion Dec. 8, 2012, during the observation of the 150th Anniversary of the Battle of Fredericksburg. The event commemorates the first amphibious assault undertaken while under fire in U.S. history when engineers from the Union Army built a pontoon bridge while under fire from Confederate Soldiers. Confederate and Union troops exchanged fire from their respective river banks as Union troops sailed across the river in pontoon boats before the majority of their forces crossed the bridge on foot. After crossing the bridge and clamoring up the banks of the Rappahannock, Union troops continued to engage Confederate forces in the streets of Fredericksburg, just as they did during the original battle 150 years ago. (Photo by Cotton Puryear, Virginia National Guard Public Affairs)Civil War reenactors portraying Union troops cross a bridge assembled across the Rappahannock River by Virginia Guard Soldiers from the Bowling Green-based 189th Engineer Company, 276th Engineer Battalion Dec. 8, 2012, during the observation of the 150th Anniversary of the Battle of Fredericksburg. The event commemorates the first amphibious assault undertaken while under fire in U.S. history when engineers from the Union Army built a pontoon bridge while under fire from Confederate Soldiers. Confederate and Union troops exchanged fire from their respective river banks as Union troops sailed across the river in pontoon boats before the majority of their forces crossed the bridge on foot. After crossing the bridge and clamoring up the banks of the Rappahannock, Union troops continued to engage Confederate forces in the streets of Fredericksburg, just as they did during the original battle 150 years ago. (Photo by Cotton Puryear, Virginia National Guard Public Affairs)