Osborne House, one of Williamstown's oldest homes, listed for sale

Osborne House, one of Williamstown's oldest homes, has hit the market.

The two storey stuccoed stone house, built in the 1850s, is one of just a handful of houses built pre 1860s in the suburb south west of Melbourne.

Osborne House was constructed by John Lamont with a two level verandah supported on masonry side walls and superposed, square-section column pairs, forming a porch like portal at the centre.

In 1,010 sqm grounds with established Pepper trees, Osborne House nine principal rooms, including a formal reception and five bedrooms.

There's also a walk down wine cellar.

Raine & Horne Williamstown agents Rosemary Jamonts and Nathan Smith have a $3.5 million guide for its September 14 auction.

The home, which hasn't traded hands for three decades, was used as a school for a long period last century.