It is practically devoid of trees, being covered with heather, gorse, and bracken where not granite rock and boulders.

[2]Private Acts of Parliament (in 1893, 1897 and 1899) allowed the BC&DWC to secure the 9,000-acre (3,600 ha) catchment area with associated access and water rights.

[3] An old name for the valley was Glen Setanta from a legend that the young Cú Chulainn spent time there.

In the 1800s it was called Happy Valley apparently due to the jollity of prospecting Cornish miners.

The name Silent Valley is supposed to derive from the absence of bird life during the long construction project.