Camp Abbot Camp Abbot was a United States Army training center located south of Bend , Oregon , United States . The center was used to train combat engineers during World War II . A large part of site has now been developed as Sunriver Resort . The rest has been incorporated into the Deschutes National Forest . The only remaining structure from Camp Abbot is the officers mess hall . Today , it is part of Sunriver Resort . It is known as the " Great Hall " , and is used for large conferences and special events . Site history . In 1855 , Secretary of War Jefferson Davis dispatched an Army Corps of Topographical Engineers survey party to look for a railroad route from the Sacramento Valley in California to the Columbia River in the Oregon Territory . This required the party to survey the Deschutes River area in central Oregon . The survey party was led by two Lieutenants , Robert Stockton Williamson and Henry Larcom Abbot . The Williamson - Abbot survey party included a geologist - botanist , a physician - naturalist , several assistant engineers , a computation specialist , a pack master , and eighteen mule packers . At Fort Reading , a military escort of eighty infantrymen and twenty cavalry troopers joined the party . The escort was commanded by Lieutenant H . G . Gibson with Lieutenants George Crook and Philip H . Sheridan leading elements of the detachment . While in central Oregon , illness forced Lieutenant Williamson to return to California . This left Lieutenant Abbot in charge of the expedition . On 4 September 1855 , Abbot and a detachment of the survey party camped at a site along the Deschutes River that would become Camp Abbot . Abbot completed the survey of central Oregon , crossed the Cascade Mountains into the Willamette Valley , and then returned to Fort Reading , arriving in mid - November 1855 . In 1857 , the Army published Abbot ' s thorough 499 page report under the title " Report of Lieut . Henry L . Abbot Upon Explorations for a Railroad Route from Sacramento Valley to the Columbia River " . World War II . During World War II , the Army needed to rapidly expand its combat engineer training . On 4 December 1942 , the War Department established a combat engineer replacement and training center along the Deschutes River south of Bend , Oregon . It was named in honor of Brigadier General Henry Larcom Abbot , who had led a survey party through the area in 1855 . The first trainees arrived at Camp Abbot in March 1943 , even before the camp was formally dedicated on 2 September 1943 . At that time , it was one of only three combat engineer training centers in the United States ; the other two being Fort Belvoir ( Virginia ) and Fort Leonard Wood ( Missouri ) . Approximately 10 , 000 soldiers were trained during each 17 week cycle . The training was conducted in three phases . The first part of the course focused on rifle marksmanship and other basic combat skills . The first phase also included special training on hand grenades , anti - tank mine s , and other combat engineering tasks . The second phase was demolition training . During that phase , trainees learned how to build and destroy bridges and other structures . The final phase was three weeks of field maneuvers carried out under combat conditions . Over 90 , 000 combat engineers were trained at Camp Abbot before the center was closed in June 1944 . Most of the camp structures were demolished shortly after the training center closed . Post - war development . In the years following World War II , a portion of the Camp Abbot property was returned to the United States Forest Service . However , approximately were sold as private land . That property changed hands a number of times , until it was purchased by John Grey in 1965 . Grey began development of Sunriver Resort , selling the first residential lots in 1968 . Today , Sunriver is a luxury resort with a 250 room lodge , three golf courses , six restaurants , and an executive airport . There are approximately 4 , 000 homes on the adjacent Sunriver property along with a small commercial district that supports the shopping needs of the community . Original structures . Today , only one original Camp Abbot building remains . The officers ' mess hall was built in 1944 by the Army Corps of Engineers under the direction of Captain John V . Banks . It still exists at its original location ; however , it is now part of Sunriver Resort , known as the " Great Hall " and is used for large conferences and special events such as banquets and weddings . The historic Great Hall is an impressive log structure measuring . It was constructed using native stone and logs cut near the building site . The Great Hall has a high ceiling with exposed beams , a large stone fireplace , and a balcony overlooking the main floor . There are also small side rooms including an intimate fireside room and a number of conference rooms . In 1993 , Sunriver Resort completed a major renovation of the Great Hall . As a result , the historic Great Hall is a modern facility with unique architectural character . The only other Camp Abbot structure to survive for an extended period was the General Patch Bridge which was constructed in 1944 by Army engineers during the Oregon Maneuver . The Oregon Maneuver was the largest military field exercise ever conducted in the Pacific Northwest . It involved over 100 , 000 army troops , many of them combat engineers based at Camp Abbot . The maneuver extended across six eastern Oregon counties . Camp Abbot was used as the exercise headquarters because of its central location and military infrastructure . The General Patch Bridge was located on Deschutes National Forest land within the boundaries of old Camp Abbott . The bridge was named for General Alexander M . Patch , who led the Oregon Maneuver . The Forest Service demolished the bridge in 2008 because the structure was unsafe .