Allynbrook is just over 208 km from Sydney, via Maitland, Paterson, Vacy and Gresford (all sealed roads). Located in a valley whose hills make up the southern slopes of the Barrington Tops National Park, Allynbrook enjoys the Allyn River fed by the pristine waters of the Barrington Tops, through the Upper Allyn River and Chichester State Forest (encompassing the Allyn River Forest Park and the Mount Allyn Flora Reserve).

With Paterson River to the west and Williams River to the east, Allynbrook is a great location from which to visit the surrounding region, including the vineyards of the Hunter region, the World Heritage Listed Barrington Tops National Park and the popular coastal waterways of Port Stephens.