Trellech is a village and parish in Monmouthshire, south-east Wales. Located 5 miles (8 km) south of Monmouth and 4 miles (6.4 km) north-north-west of Tintern, Trellech lies on a plateau above the Wye Valley on the southern fringes of 320 acres (130 ha) of woodland in an Area of Outstanding Natural Beauty. Three Bronze Age standing stones are situated in the village, known as Harold's Stones, which overlook the historic church of St Nicholas, a Grade I listed building.

Gwent Wildlife Trust (GWT) is a wildlife trust covering the area between the lower Wye and Rhymney rivers which forms the vice county of Monmouthshire in south-east Wales. It is a registered charity and a member of the Wildlife Trusts Partnership.