This image shows the elevation contours for the region around the Boonsboro Turnpike. As always, the white lines mark modern roads: Maryland Route 34 (the modern designation of the Boonsboro Turnpike) runs from the site of the middle bridge (near the upper right corner) to the outskirts of Sharpsburg (the mid left of the image). The tour road that runs from the Sunken Road to the Sherrick farm runs top to bottom across the middle of the image.

Several important features are visible: the cigar-shaped hill is located toward the upper right hand side of the image, just north of the picnic area (the picnic area is the loop which dips down from Route 34 on the right-hand side of the image). Note the drainage system which runs down from the Piper farm and cuts around the cigar-shaped hill to the west and south; on the south side of the turnpike it widens and deepens considerably where it empties into the Antietam.

Further to the west, the turnpike is dominated by Piper's Hill (just to the northwest of the road) and Cemetery Hill. All but ignored by battle historians, Piper's hill was occupied by Confederate infantry and artillery throughout the afternoon, ready to resist any Federal move up the turnpike. Although no real Federal advance came up the turnpike, Pleasonton's cavalry did push skirmishers west of the Newcomer farm where they engaged with Confederates on Piper's hill. At around 3:00 pm, remnants of Colquitt's, Garland's, and G.T Anderson's brigades were moved from the now quiet Sunken Road region to reenforce Piper's hill. Other than this half-hearted push by the Federal cavalry, however, no concerted Federal drive up the Boonsboro Turnpike took place.