The Herculanean House is situated near what was originally the northwestern corner of the walled garden near the house. It was a perfect replica in the classical Roman style, with a courtyard and interior paved with tiles copied from a design found during the excavations of the original Herculaneum. The interior of the Herculaneum was entered through a wide doorway, defined by pillars.

The windows of the little house were of stained glass, and overlooked the romantic valley of the Naniken River below.

Also in the river valley, there is an unfinished bridge in the Roman Composite Order, in the form of a temple approach. This approach was the main link to the walk directly to Watermill Road. There were several grottoes and bowers through the Naniken valley, and a Druidic circle of basaltic rocks taken from the Giant's Causeway.