In 1839 the Duke of Leinster’s grandson, William, became the 23rd Baron de Ros and decided to make his principal seat in the port and village of Strangford which he had inherited.
This was the original entrance to his estate and led the way around the outside of the village to the family home which he built, in place of an earlier mansion, at Old Court in 1844.
In 1853 Lord Dufferin and Clandeboye planted the avenue as a wedding gift to Baron de Ros’s son Dudley and his new wife, Lady Elizabeth Egerton. For this fine present he paid for the widening and improvement of the main avenue to Old Court as well as the planting of lime trees.
It is now a public path over the wooded Compass Hill, through the Squeeze Gut to Castle Street, Strangford.
In the 1860s this avenue was on the same level as the road from which it leads. However, horses found the climb difficult when pulling cargoes of potatoes and coal from the harbour so Lord de Ros had the road lowered and a new access road built.
This means that the gatehouse and this entrance to Dufferin Avenue must now be accessed via stone steps.