Boundary Wall to Glynllifon Park

The boundary wall to Glynllifon Park is a 10-kilometer-long rubble wall that runs along the east side of the A499, following the winding paths of the narrow roads between Groeslon and Penygroes. It also extends west of the A487 and a disused railway line. The wall features pointed, slightly projecting coping and reaches a height of up to 4 meters.

On the west side, the wall runs alongside the main A499 road, with lodges at either end. It includes a prominent 'triumphal arch' entrance set back near the midpoint, which is listed separately, as well as a simple entrance with gate piers near the south end. The corner entrances are pointed-arched, with the northern entrance being stepped and gabled, while the southern entrance opens onto one of the drives. The north side of the wall winds along the by-road and includes the East Lodge, which has a similarly pointed and gabled entrance arch leading to the northern drive. Just west of the junction with the A487, the wall turns sharply southeast.

To the south, changes in the masonry suggest that the wall has been doubled in height. It follows the bends of the by-road for about 1 kilometer before forking northeast, bordering woodland. On the east side, the wall aligns with the old turnpike road, which was re-routed when the railway was constructed. A lane from the A487 provides access to Upper Lodge and the east drive. At the northern end, the wall, disused railway line, and road are closely situated; although the Upper Lodge is now in ruins, the pointed archway remains intact.