The Architectural Conservancy of Ontario (ACO) was founded in 1933. The organization was initiated by the saving of Barnum House near Grafton, which is now owned and operated by the Ontario Heritage Trust. Today, the ACO operates as a decentralized organization with 25 branches across Ontario and a central provincial headquarters located in Toronto. The ACO has helped to save hundreds of heritage buildings across Ontario, and has raised awareness of the importance of preserving Ontario’s provincial, municipal, and community heritage. As the first organization to do such work, ACO pressed for heritage legislation and funding in Ontario, and has been followed in the field by such outstanding organizations as the Ontario Heritage Trust, Community Heritage Ontario, and the Canadian Association of Heritage Professionals.

ACO Port Hope receives charitable donations, and manages charitable fundraising events, such as the ACO Antique Auction. In turn, ACO Port Hope makes grants available for restoration projects in the Town of Port Hope.

The Port Hope branch was formed in the early 1960s. Since then, it has become one of the most active and financially successful of the ACO branches with almost 500 members. In 2002, the Municipality of Port Hope was recognized as possessing the finest heritage main street in Ontario.

The Branch owns the historic “Little Station,” one of the first railway stations in the Town of Port Hope, and leases and operates the Union Cemetery Chapel and Caretaker’s Cottage from the Municipality of Port Hope. Over the years, the Port Hope Branch has been involved with other partners in the restoration of the historic Port Hope Grand Trunk railway station, which is now used by VIA Rail.

At its annual general meeting in 2012, the membership overwhelmingly voted to commit up to $500,000 in the form of grants and loans to assist with practical architectural restoration projects in Port Hope’s downtown core. Scaffolding went up at the commercial block at Walton and Ontario streets as the first project, and bricks were cleaned and re-pointed together with other masonry repairs that were addressed at the same time. Heritage windows were also restored. Since then, similar preservation work has been completed on about 15 buildings in the heritage downtown core.