Building London loves old paving. It’s may be only 2 dimensional, it doesn’t soar and it’s usually only one material but it can be quite beautiful as well as functional and utilitarian. The patterns seen at e.g. Albury Street in Deptford or Three Mills Island show that gloriously. But it can be both hard to date and harder to pinpoint origins, especially with granite setts. And London with it’s constant pavement and roadway repairs and redevelopments, finding historic road surfaces is hard. The probably 18thC road at Upper Watergate Street [see https://buildinglondon.blog/2021/12/12/21-upper-watergate-street-the-oldest-street-surface-in-london/ ] is pretty unique due to the large size of it’s boulders so Building London has long been on the look-out for something similar. Deans Yard appears similar and investigation shows that while on one level it’s not that old, it’s origin may be much older!  

Dean’s Yard [1] is part of the Westminster Abbey [2] precincts and dates back to the 13thC. And bordering the grassed central area, and a tarmaced road surface, on the southern sides is a cobbled border, not a pavement for pedestrians but part of the road surface. And they are not small cobbles but quite large cobbles. And cobblestone [3] street surfaces in London are very rare. Some irregularly and widely spaced cobble areas have appeared in London since the 1960s but this are deterrents, designed to stop people walking on those areas rather than as paving. And cobbles are really not great for walking on! Unlike granite or Purbeck setts cobbles are not flat and so are uncomfortable to walk on and bumpy for wooden or iron rimmed carts and carriages.

A Mechanics Manual on ‘Road and Footpath Construction’ of 1904 tells us “The old fashioned cobble-stone or bouldering, still to be met with in small country towns, has many defects. It is very unpleasant to travel over, and it is, at the same time, very noisy; moreover as the rounded boulders cannot be packed close together owing to their shape, great spaces are left, in which horse droppings and filth accumulate. Water stands readily in the hollows and to get rid of it a large amount of cross fall has to be given. The only advantage in such a system of paving lies in its great durability.” [4]

It’s worth  quoting here The Paving Expert who highlight the difference between setts – dressed, oblong, squared stone whether granite, limestone or any other stone, and cobbles – stones produced naturally in rivers, under glaciers or on beaches. [5]

And they also describe the difference between cobbles, boulders and pebbles. “Geologists … define cobbles as ’rounded stones between 64mm and 256mm in size’ . Those cobbles between 64 and 128mm are “small cobbles”, while those between 128 and 256mm are … “large cobbles”. Rocks bigger than 256mm are … boulders, and those less than 64mm are pebbles.” [6] and how they are laid! [7]

But cobbles were very commonly used for paving from Roman, through medieval times till recent centuries, as they were easily available from rivers and beaches. “Villages would rarely be ‘pitched and paved’ throughout, especially in areas where stone was unavailable or unsuitable. Flagstones might be used in the churchyard and outside some buildings, but cobbles would predominate.” [8] [9]

Nowadays they are rare and only kept in historic conservation areas. Cobbles are particularly bad for cycling on, and again it’s worth noting that the infamously tough cycling cobble races like Paris-Roubaix are on setts, also tough to cycle on, not cobbles. [10]

So how old are the large cobble surfaces in Dean’s Yard then? Almost certainly from before the advent of the mass use of granite setts, so early 19thC at the latest and possibly much earlier. In the 17th and 18thC Purbeck setts were often used in London, so why not those? Could they then predate the 17thC? And Deans Yard has been in existence, in one form or another, for 100s of years so could they be older?

Tim Tatton-Brown and John Crook’s survey of Dean’s Yard in 2020, for a planning application for Westminster School, describes the  history of the area and genesis of the modern square[11] and show it going back to the medieval period as a yard within the precincts of the abbey, though changing in size and shape, with buildings coming and going, till the current square was established in 1815.

So 1815 would therefore seem to be the obvious date to date the cobbles to then. Except. There are drawings and paintings before that date showing cobbles in other parts of the square. Could then the existing cobbles pre-date their current positioning?

And, in the alleyways that lead off Dean’s Yard, one under the Blackstole Tower into the old Abbey buildings, and the other into Little Dean’s Yard, both now part of Westminster School there are also cobbles. And, these buildings are late 14thC though that does not mean the paving is. [12]

And in Little Dean’s Yard cobbles were exposed during recent repairs, which were under 19thC paving.

So while clearly the current positioning of these cobbles is probably from 1815 it’s also probable that maybe many parts of Dean’s Yard did once have cobbles and therefore it is possible that the ones we can see now were actually first laid in the area in between the 14th and 17thCs.

And we see how things ‘move’ recently. In 2015 the existing cobbles were all dug up as part of improving the road way. And while they have been relaid are they now entirely original? Clearly yes on one level. If a medieval barn is taken down and rebuilt in a museum it is still a medieval barn. But it shows that these cobbles could have moved from somewhere else in the square over the centuries. Also note from the photo the size and irregularity of the stones, which suggests they are older rather than more recent.

And is it also  possible that there are many more cobbles in the square now with tarmac, or grass, covering them? This was not shown by the road works or the recent excavations in the north west corner of the square which frustrating did find “cobbles” but then specifies them as “Granite and basalt setts along with York stone paving were recovered from the unstratified layers. It is probable that these represent ex situ 19th-century cobbling.”, so not cobbles at all. [13]

So, to conclude, it looks like these cobbles will have to be dated as 1815 when Dean’s Yard was laid out as a complete square, though it is possible that the cobbles seen today were actually first used far earlier in other parts of the square and may have been collected to be used in the square many 100s of years ago, even back to the 14thC!

And where did they come from? Looking at the stones both in situ and in the picture of them dug up from 2015 they do not look like beach cobbles seen e.g. in Brighton though some may be. Geo Essex notes “Blocks and cobbles of building material were dug from local pits, cleared from the land or transported up rivers from seashores.” [14]
Middlesex would have similar Quarternary desposits from which glaical cobbles would have been found.

And in Essex these cobbles include a very wide range of rocks from a wide range of geological time periods “The cobbles … include various sandstones, quartz, basalt, granites, rhyolite, porphyry, Carboniferous sandstones, Carboniferous limestones and Jurassic limestones.” and again, “Pebbles and cobbles (Field Stone) – The Quaternary fluvial deposits of Essex (notably those belonging to the Kesgrave Catchment Subgroup) encompass a diverse range of poorly sorted, relatively soft and unconsolidated sediments which have been exploited (by means of pits and larger excavations) for construction materials. The harder pebbles and cobbles yielded as a by-product of this activity served as an important and convenient source of stone for local buildings and walls. Pebbles and cobbles were also cleared from nearby field surfaces and used as building materials.
The pebbles and cobbles vary considerably in composition and include: chert (orange-brown to pale brown coloured); vein quartz (white or iron-stained pink to brown and sometimes exhibiting very small quartz crystals); quartzite (often liver- or brownish-coloured ‘Bunter’ pebbles derived from the Triassic Chester Formation of the Midlands); chalk (usually from Glacial Till deposits); various limestones (including Jurassic and Carboniferous limestones); Carboniferous sandstones; igneous and metamorphic rocks (e.g. dolerite, granite or ‘Cornish Rock’, very tough and compact, veined or brecciated) and very occasionally red and yellow jasper or cream-coloured chalcedony.” [15]

Some of these stones may have come very long distances. A boulder from Warren Farm Quarry was found to have come from Northumberland, carried along by glaciers. [16]

They may well have come from the Thames shore, brought up river from the coast or dug from gravels and sands anyd maybe somewhere in the Westminster Abbey archives there is order for a boat load of cobbles to be delivered to Westminster Abbey.

Nigel Woodcock, in his presentation on ‘Building Stone Use in Cambridge 1040 to 1770’ discusses a cobble path, he calls the stones ‘Fieldstones’, from the old Clare College and dates it at pre-Black Death on the basis that the large fall in population meant stone was no longer collected from fields for several centuries after, and by which time other stones for paving were being used. So some cobbles at Westminster Abbey and Dean’s Yard may well then date before then too.

Visiting

Dean’s Yard is open to the public
The cobbles are clear to see in the southern sides of the square.
The alleyways are private but the cobbles can be seen in them.

References
[1] https://en.wikipedia.org/wiki/Dean%27s_Yard  
[2] https://en.wikipedia.org/wiki/Westminster_Abbey
[3] https://en.wikipedia.org/wiki/Cobblestone
[4] Road and Footpath Construction – Mechanics Manuals 1904 https://archive.org/stream/roadandfootpath00haslgoog/roadandfootpath00haslgoog_djvu.txt
[5] https://www.pavingexpert.com/setts01
[6] https://www.pavingexpert.com/cobble01
[7] https://www.pavingexpert.com/cobble02
[8] https://www.designingbuildings.co.uk/wiki/Road_construction#Paving_construction
[9] http://ihbconline.co.uk/context/152/12/
[10] https://www.rouleur.cc/blogs/the-rouleur-journal/the-joy-of-setts-how-cobbled-roads-have-come-to-define-the-most-exciting-classics
[11] Weston Building (3 and 3a Deans Yard), Westminster School, ‘A Survey of the below-ground archaeology of the Dean’s Yard area’, September–October 2020, Tim Tatton-Brown and John Crook
[12] https://www.british-history.ac.uk/rchme/london/vol1/pp76-93https://historicengland.org.uk/listing/the-list/list-entry/1219626
[13] Excavations In The North-West Corner Of Dean’s Yard, Westminster Abbey, Paw B Jorgensen London and Middlesex Archaeological Society Transactions, 66 (2015), 79—136 http://www.lamas.org.uk/images/documents/Transactions66/079-136%20Deans%20Yard.pdf
[14] http://www.geoessex.org.uk/essex-geology/
[15] https://www2.bgs.ac.uk/mineralsuk/download/EHCountyAtlases/Essex_Building_Stone_Atlas.pdf
[16] http://londongeopartnership.org.uk/wp/wp-content/uploads/2018/08/Guide-to-Londons-Geological-Sites-Final-Sept-2014-reduced-size.pdf
[17] Building Stone Use in Cambridge 1040 to 1770 at 37.00 https://www.youtube.com/watch?v=9sr03fFfWgg&ab_channel=ClareCollege%2CCambridge