Highwic is a well-preserved Carpenter Gothic mansion, located on the fringes of colonial Auckland. Built for one of the wealthiest landowners in the region, it was erected in an elevated position looking out over the small nineteenth-century township of Newmarket. The earliest dwelling on the site may have been constructed soon after 1850 by William Hay (1805-1874), who was a member of the Auckland Provincial Council. In 1862, the land was sold to the Buckland family, who immediately built a new dwelling that was added to substantially over the years. Alfred Buckland (1825-1903) was an auctioneer with extensive connections in the wool trade, having arrived from Devon, England in 1850. In 1858 he held the first ever public auction of wool in New Zealand and by the 1880s was considered to be the largest private landholder in Auckland Province. As well as his substantial fortune, Alfred was also known for his large family. Twice married, he produced seven daughters and three sons with his first wife, Eliza Wallen (1825-1866), before having a further seven daughters and four sons with Matilda Frodsham (1847-1932).

The Bucklands' Highwic probably began as a six- or seven-roomed timber villa, with outbuildings for the use of servants and other employees. It was copied from an American pattern book design published in 1850 by A.J. Downing, adopting a highly ornamental Carpenter Gothic style. This marked it out from most other dwellings of the period, which were generally inspired by Georgian architecture. Carpenter Gothic was characterised by its steep gables, pronounced bargeboards and extensive use of timber for structural and decorative elements. It is a largely domestic version of Gothic Revival and originated in the USA, where it was often associated with the creation of 'new' wealth. Gothic Revival was used by certain institutions within the colonial establishment in 1860s Auckland, notably those connected to the Anglican Church and law and order. Surrounded by extensive gardens, the house was successively enlarged in the 1870s and 1880s as the Bucklands' fortunes grew and family expanded. At its grandest, the building included a large room capable of holding balls, a service yard, seven bedrooms and a boys' dormitory, with outside stables, a coach-house, a billiard room and several other garden structures. A few minor alterations were made by family descendants, who lived in the house until 1978, after which the property was jointly purchased by the New Zealand Historic Places Trust/Pouhere Taonga and Auckland City Council.

The main dwelling at Highwic is considered to be one of New Zealand's finest Carpenter Gothic houses, and is significant as a rare example of an architectural style more commonly found on the east coast of America. The dwelling and its outbuildings have considerable importance for the way in which they demonstrate the development of a colonial country house and its grounds in the nineteenth century and later. They are important for the insights they offer on family life, including domestic service, gender roles and attitudes to children, as well as garden history and - in the case of the stables - the history of horse-drawn transport. They also afford a record of constructional details, joinery, hardware and decorative finishes of the mid-nineteenth to mid-twentieth centuries. The buildings and site have connections to people and activities of local and national importance, and are closely linked with the development of the Newmarket area. Highwic is held in high public esteem, having been visited by large numbers of people since it opened as a house museum in 1981. It is important for its association with archaeological deposits and historic plantings in its extensive gardens, and for its aesthetic appearance and setting.