Now a National Historic Site (1994), Gillies Grove is an expanse (56.5 acres) of old growth forest (sugar maple, yellow birch, American beech, eastern hemlock, and basswood) and a rare remnant of the magnificent forests that once covered the region. It is also home to Ontario’s tallest tree, a white pine, at approximately 45 metres. Gillies Grove is located in the northern outskirts of Arnprior. For more than 125 years, the McLachlins and the Gillies, two great lumbering families, owned and conserved the grove. In a clearing, the Gillies built a fine, Colonial Revival home in 1937 to showcase the white pine products grown, harvested, and milled in the area. Unfortunately, the house is now in private hands and no longer accessible to the public. Gillies Grove, on the other hand, is owned by the Nature Conservancy of Canada and open to all. It is managed with the help of volunteers and definitely work a visit. A network of 27 public trails runs through the grove. The central trail (2.7 kilometres) runs off Ottawa Street.