I had wondered if there might be some interest/value in a "Connection" for "WHS without a Buffer Zone" so have been doing a bit of background investigation into just how many sites there might be in this state of "ungrace"!!

For many of the earlier years of the WHS scheme, properties were normally inscribed without "Buffer Zones" even though the Operational Guidelines (OG) referred to the concept. As time has progressed the OGs have been strengthened but still do not require that there be a Buffer Zone. However any nomination without one must state why one is not required. And, for some years, the vast majority of inscribed sites have included a Buffer Zone in their documentation.

Since these early years there has also been a significant retrospective catch-up by which many properties have acquired Buffer Zones which have been presented to the WHC. The initiative often arises where there has been a report on the state of conservation or a Reactive monitoring visit. Koln was something of a watershed as the lack of any Buffer Zone was blamed for the situation whereby the nearby tower blocks across the Rhine were able to be built – Germany provided a Buffer zone for the cathedral in 2008!

Indeed, most sites so requested seem to have complied with at least the "letter" of the request but there have been a few "causes celebres" where a States Party has tried to hold the line that no buffer zone is required – I think particularly of the Tower of London and Westminster and it was these I thought it might be interesting to highlight via a "Connection".

The existence of a UNESCO-recognised buffer zone is of course no guarantee that it will be properly maintained or that it will achieve the results hoped of it – high rise buildings well outside a buffer zone can be regarded as having worse impacts than developments inside the zone viz St Petersberg and Seville

One slight surprise which my researches have identified, has been that NONE of the US WHS has a buffer zone. The most recently inscribed (Papahanaumokuakea) was able, fairly easily, to argue that, as the inscribed area already covered vast areas of the ocean, nothing further was required. Interestingly, however, the withdrawn Mt Vernon nomination DID include a small buffer zone – but this was a bit suspect as it was really part of the property itself!! Nevertheless its existence was indicative of how much the nomination was trying stick to the rules despite the fact the US has great problems limiting activities outside National Parks/Monuments etc.

A problem I have discovered with having this "Connection" is that of the difficulty of "proving" a negative. The proposition would need to be expressed in positive terms "A site which lacks any evidence of a buffer zone in its documentation" and/or "A site whose documentation refers to the lack of a Buffer zone". Even this can prove difficult – Paris, for instance, is described in the 2006 Periodic Report as "Zone tampon : aucune zone tampon n'a été définie mais une proposition de zone tampon a été faite par l'Etat partie". However, 6 years later, I can find absolutely NO evidence of any "zone tampon" having been officially defined!

One document ( http://whc.unesco.org/documents/publi_wh_papers_25.pdf ) unearthed by my researches which might be of general interest to Forum readers, is the report of an "International Expert Meeting on World Heritage and Buffer Zones" which met in 2008 and whose recommendations were discussed at that year's WHC. I personally hadn't been aware of it and found the issues it discusses and the "history" on this subject contained within it, well worth reading. It also contains a number of examples of sites not having a(n Official UNESCO-recognised) buffer zone – though some of these (E.g Koln) are now out of date.
a. Kilwa Kisiwani
b. Wet Tropics of Queensland
c. L'Anse aux Meadows
d. Belovezhskaya Pushcha /Bialowieza Forest
e. Berne
f. Jungfrau/Aletsch
g. Mammoth Cave
h. Missions of the Guaranies (??? Possibly)
i. Luang Prabang

In the case of the Cologne Cathedral they have been a bit excessive in terms of the buffer zone, I think. It is 258 hectares in size, the southernmost point is about 2 km from the cathedral.
From the decision document in 2008 http://whc.unesco.org/archive/2008/whc08-32com-inf8B1ADDe.pdf , No 292rev):
„ICOMOS notes that the definition of the new buffer zone is purely geographical. It could also be supported by historical criteria, particularly on the western limit of the western part of the buffer zone on the left bank. It could follow the medieval boundary of the historic town, ..."

That's strange, because the medieval boundaries are hardly visible in Cologne.

In Aachen and Speyer no buffer zone was required. From the Periodic Reporting (Cycle 1) Section II Summary in 2006:
„The site is surrounded by protected monuments which guarantee sufficient protection" (Aachen)
„The cathedral and the surrounding area are protected as a monument zone pursuant to the Law on the Protection of Monuments of Land Rhineland-Palatinate" (Speyer)
I'm not sure how large these protected areas are, but surely they are less than 258 hectares.

In Würzburg a rather small buffer zone was approved, which includes just the streets surrounding the residence and a few buildings.

For some of the early French inscriptions (Chartres, Reims, Amiens) WHC recommended in 2006 a buffer zone of 500 m around the core building. Although probably appropriate, a "purely geographical definition" without supported by "historical criteria":
„L'Etat partie aimerait définir une zone tampon bien que la législation en vigueur protège les environs de la cathédrale sur un rayon de 500 m" (from the Periodic Reporting (Cycle 1) Section II Summary)

Pisa provided an interesting solution. They defined the historic city centre as the buffer zone which is protected by law. Sounds reasonable. However, the cathedral lies at the periphery of the city centre. Thus, the buffer zone is about 1 km in east and south direction, but only a few metres in north and west direction.

These are just a few examples for single monuments, a category where the definition of a buffer zone is rather easy compared to historical city centres or cultural landscapes.
All in all rather confusing, consistent requirements for buffer zones would be more useful.

Thanks for the extra detailed information on buffer zones Hubert

A couple of points
There seems to be a difference in memory across the 2 documents cited above regarding the Koln Cathedral buffer zone
a. The "International Expert Meeting on World Heritage and Buffer Zones" includes this comment
"Christof Machat of Germany, with reference to conflicts surrounding development proposals near the Cologne Cathedral notes that the Cathedral was inscribed in 1996 without a buffer zone, and that although the Committee requested establishment of a buffer zone at the time of inscription, none has ever been established. Machat notes arguments advanced by the city conservator in 1980 that a buffer zone was not necessary as "the cathedral is protecting itself ", even though the "protection areas" established by the Protection Law of June 1, 1980, were never used, and resulted in the vulnerability of the Cathedral to proposals to build large scale towers which would have negative impacts on views of the cathedral."
b. The 2008 Decision document states
"The buffer zone boundaries were defined in 1996, as a complementary measure for which a request was made to the State Party by the World Heritage Committee, to enable inscription on the List. The initial buffer zone was limited to the area immediately adjoining the cathedral, on the right bank of the Rhine, covering a surface area of 16.8 ha."

So the first says that a buffer zone wasn't defined and the second that a small area on the rgiht bank next to the Cathedral was defined!!

On another matter raised by your examples - there seems to be a clear preference by ICOMOS for Buffer Zones which are supported by Historical Criteria - indeed, the 2008 decision document regarding the buffer zone proposed by Koln and accepted at that time goes even further than the quote you provide "ICOMOS recommends that reflection should continue concerning the limits of an extended buffer zone based on historic criteria."

I wonder what the justification for this could be? Every document on this matter makes it absolutely clear that any buffer zone should be free of OUV - if there were to be anything within it which had OUV then it should be part of the inscribed site. It would seem that ICOMOS is trying to maintain some historic value from buffer zones - but on what basis?
As your Pisa example shows, a buffer zone based on a historic boundary can be virtually useless - and the examples of Seville etc show that "visibility" from the WHS is the main issue to be cared for. This of course means that even quite large buffer zones are useless where high rise buildings are concerned. The Expert meeting plays with the idea of different types of buffer zones - even "rings" of them (and cites the example of the Rhaeitan Railway).

As you say there is a lot of muddled and unclear thinking and "custom" on buffer Zones -despite the Expert Group's input

I have posted the following under this Topic as being more relevant -
a. I was not aware that Semmering also had a "layered buffer zone"
b. In fact as far as I can make out it did NOT when first inscribed in 1998.
c. I haven't found any mention of a "Buffer Zone" in either the Nomination File or the AB Evaluation, though the former does contain a couple of maps which show a thick blue line following the railway and a hatched area on either side reaching some way into the surrounding countryside. The is no "legend" so these could represent the railway line etc with the entire hatched area being "inscribed" or the core area (consisting of the line etc) and a single buffer zone.
d. What is absolutely clear is that the site was inscribed as a "Cultural Landscape". This is confirmed in the AB eval thus "It may also be considered to be a Linear Cultural Landscape as defined in the Operational Guidleines 1995..." The Nomination File frequently refers to the CL and makes much of the architecture of the villas and hotels which grew up in that CL around the railway (over half of the Nom File pages!). In that respect the lack of any inclusion of that surrounding important surrounding CL seems even more strange than in the case of the Rhaetian example!
e. Today however a search in the UNESCO site on "CL" among the currently inscribed sites returns 98 properties - but these do NOT include the Semmering! It would appear therefore that neither UNESCO nor Austria regard this site as a CL whatever the Nomination and Inscription documentation might say!
f. In July 2008 at the Quebec WHC 2008 Switzerland/Italy gained inscription for the somewhat "similar" Rhaetian Railway whose tabled Nomination File included the "layered buffer zone" concept which has led to this discussion. I have just noticed that some of the Chapters are described as having been "revised" in Feb 2008
g. However, in March 2008 an "International Expert Meeting on UNESCO and Buffer Zones" had been held in Davos - and it appears that this was not coincidental to the development of the "Layered Buffer Zone concept" as included in the Rhaetian Nom File! I quote from the Preface to the papers for that Expert Meeting - "Switzerland proposed (the Rhaetian Railway) in 2008 for inscription on the World Heritage List. It was ultimately important issues relating to this project which resulted in the international expert meeting on buffer zones in Davos issues relating to this project which resulted in the international expert meeting on buffer zones in Davos."
and
" During preparations on the nomination of the Rhaetian Railway, there were intense debates on the issue of its buffer zone ultimately resulting in a specific solution. The property (formerly called the core zone) consists of the railway line, totaling 128 km, to include stations and related buildings or construction such as sheds or platforms, and the auxiliary technical structures along the line. The landscape surrounding the railway supports the
outstanding universal value of the object: One the one hand, travelers truly "experience" the environment with the railway and, on the other, the railway itself has become an integral part of the landscape"
There is then more discussion on the "Rhaetian solution" which is probably best read from within the paper - http://whc.unesco.org/document/101967
h. At the 2009 WHC under the Agenda Item "Clarifications of property boundaries and sizes by States Parties in response to the Retrospective Inventory" Austria presented a map (dated Nov 2008) clarifying the boundaries of the Semmering Railway. It is THIS map which introduces the concept of layered buffer zones to the Semmering Railway based on the principles accepted the previous year for the Rhaetian Railway - though not exactly the same definitions. See this download - https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved= 0ahUKEwjg2oaClt_PAhXNSxoKHcpuBDEQFggcMAA&url=http%3A%2F%2Fwhc.unesco.org%2Fdocument%2 F102282&usg=AFQjCNHckaJgN1JFzYChKac0LNBk38bftw&bvm=bv.135974163,d.d2s
i. Which leaves the question as to whether there are any other WHS which have adopted this approach. Any such WHS will have to have been inscribed AFTER 2008. One possibility might have been the 2 extensions to the Mountain Railways of India but these occurred in 2005 and 2008 and, in any case, that inscription does NOT claim OUV from the surrounding landscape.