The suburb of Rathfarnham nestles at the foot of the Dublin mountains. Situated on the southside of the city it derives its names from Rath i.e. fort of Farnham, an Celtic Chieftain. An interesting features of Rathfarnham are the secret tunnels. One leads from the castle to an exit at the present Castle Golf Club. Another led from the castle to the Church of Ireland in the village - this tunnel was only discovered in 1987. Both have been closed off.