Lower Hael Wood is a semi-ancient woodland and Site of Special Scientific Interest (SSSI), noted for its biological characteristics, in Monmouthshire, south east Wales.

[2] Early industry was also present on the site, with a grist mill on the southern slope and evidence of quarries also found.

[3] The 17.6-hectare (43-acre) SSSI, notified in 1981, is located within the community of Trellech United, on the banks of the River Wye, 3.5 miles (5.6 km) south-east of the town of Monmouth.

As with other woodland in the Wye Valley Area of Outstanding Natural Beauty, Lower Hael Wood contains many local and rare tree species.

The main tree species found on the site include ash (Fraxinus excelsior), common beech (Fagus sylvatica), small-leaved lime (Tilia cordata) and wych elm (Ulmus glabra), as well as English oak (Quercus robur) and sessile oak (Quercus petraea).