During the Atlanta Campaign, Sherman maneuvered Johnston's Confederate army out of several successive defensive positions in Cobb County. This strategy spared the Union army from making costly frontal attacks on the well-situated Confederates. Sherman first found Johnston's army entrenched in the Marietta area on June 9. The Confederate's had established defensive lines along Brushy, Pine, and Lost Mountains. Sherman extended his forces beyond the Confederate lines, causing a partial Rebel withdrawal to another line of positions. After further pressure and skirmishing from Union forces, Johnston withdrew to an arc-shaped position centered on Kennesaw Mountain on June 18 and 19. Sherman made some unsuccessful attacks on this position but eventually extended the line on his right and forced Johnston to withdrawal from the Marietta area on July 2-3.