The tunnel is approximately 180 metres long, and was originally built five metres high. However, with the introduction of stock trucks and trailers onto the road, this was not high enough. In 1985, Colin Boyd (from Inglewood Metal Supplies) lowered the floor a further two metres.
About two decades ago, a witty traveler nailed up a sign re-naming the Moki Tunnel as the"Hobbit's Hole". This nickname is still used today. The Moki Tunnel is a fine example of the unusual and well thought-out work completed by the road engineers and surveyors of early New Zealand. It has been appreciated by many travelers on the road, and is seen as one of the remote tourist attractions of Taranaki.