The answer to this question matters a lot in some instances. From 1992, the Lighthouse Society of Great Britain  offered a free information service. In 2005, the group’s publication, the Lighthouse Encyclopaedia, was in its eighth edition . The latter publication was inaccurately titled because it contained far more than just a list of lighthouses. Yet, what are the criteria for deciding whether a structure is or is not a lighthouse? It is an apparently innocent question, yet, because of the inconsistencies of usage I have already alluded to, it is impossible for one ‘expert’ to provide an exact answer to a question that, in the English language at least, could not be argued against by another ‘expert’.
It is not possible to unambiguously answer such questions as, "How many lighthouses are there in Canada?" or "What was the first lighthouse ever built?" The author was faced with just such a dilemma when writing a book . The solution was to write about an early lighthouse – the Pharos at Alexandria. This structure is one of the Seven Wonders of the Ancient World, a fact that might lead to the conclusion that it was quite unlike anything that had gone before. Was it, therefore, the first lighthouse? We can, with certainty, say only that it was the first lighthouse about which there is no doubt of its existence. Surely, there must have been similar, but lesser, structures preceding it to act as design templates? The inclusion of the Pharos in the list of Seven Wonders was surely made on the basis of its grandeur and magnitude, rather than its innovation in function. In answer to the question as to which was the first lighthouse, we are forced to conclude that we are unable to provide an answer that is not fuzzy. Neither can we give an exact number for the total of lighthouses in Canada – or anywhere else, for that matter. Yet that is what some of us are frequently asked to do.
The Statue of Liberty is often described as an American lighthouse , a statement that brings great surprise to many. In fact, the US Light-house Board officially listed the Statue of Liberty as a lighthouse for a period of about 15 years (1886-1902). In 1877, Congress authorised the President to accept the Statue from France and to maintain it as a beacon. It was dedicated by President Grover Cleveland on 28 October 1886 and a little over two weeks later was turned over to the Board. It was first lighted on 22 November 1886, and remained in use as a lighthouse until 1 March 1902. In this unusual example, the role played by the Statue of Liberty in American culture is of far greater significance than that of a mere lighthouse. However, it could also be argued that the values associated with the Statue of Liberty are the very same values that bring warmth and comfort to most people when they think of lighthouses in general. It should therefore be possible to devise a definition of a lighthouse that includes such a structure.
Consider the question, "What lighthouses are there in New Brunswick that I can visit?" If, whilst working for the New Brunswick Office of Tourism, we recommend that a person should visit a certain location, we want him to be pleased when he makes the effort and goes there, especially in cases where great distances must be travelled. It is possible for entire days of precious vacation to be wasted! On the other hand, we do not want the lighthouse explorer to report back after his vacation and angrily say, "Why didn't you tell me about the lighthouse at Caraquet?"
From the point of view of tourist information – or, indeed, heritage, in general - not only are we unsure what structures to place in the category of 'lighthouse', but we are unsure whether the prospective visitor will be able to get close to it, inside it, or, in the case of offshore rock lights, whether a boat is needed. It might be OK for some tourists to hire a helicopter, but not for most of us! So, the provision of good tourist information is beset with difficulties. Leaving aside the use of the term lighthouse in the context of navigation, a clear and consistent definition is most important in the wider social context. We will concentrate this discussion on the definition of a lighthouse, rather than on what constitutes a "visit".