Fossil Coast Explores Plymouth’s Geo Trail at The Royal William Yard

Are you visiting Plymouth this summer? Attending a meeting or just looking for a family friendly activity lasting about an hour? The University of Plymouth and Urban Splash the company responsible for the wonderful regeneration of the Royal William Yard have Teamed up to create a free and interactive Geo Trail.

The Royal William Yard Geo Trail guides the intrepid adventurer for about hour through journey dating back the Devonian Period some 380 million years ago using the back drop of Plymouth's historic naval buildings and landscape.

Collect your GeoTrail Guide at the Gatehouse

On a sunny day in late July the Team at Fossil Coast Drinks Co journeyed to Plymouth to explore the Geo Trail.

As you walk from Plymouth's train station towards The Royal William Yard you will pass through an area known Stonehouse .

At this point it becomes abundantly obvious how locally quarried Devonian limestone, granite and slate has been used as building and paving stone.

The Limestone geology of the South West is also the inspiration behind our own Lime Stone London Dry Gin.

As you arrive at The Royal William Yard do pop into the Gatehouse on the left and collect a free leaflet on the GeoTrail.

Before we dive deep in to GeoTrail lets take a moment to understand the context of the Devonian Period, the local Devonian geology and also understand the roll The Royal William Yard played in our own naval maritime heritage.

The Devonian Period

The Devonian Period, spans between 419.2 million and 358.9 million years ago and was the fourth period of the Palaeozoic Era and the earliest of three geologic eras of the Phanerozoic Eon. The Devonian Period spanned 60.3 million years from the end of the Silurian to the beginning of the Carboniferous.

Tropical Plymouth limestone fossil corals

The Devonian Period is the only geological age named after an English county. The Devonian is named after the county of Devon and was designated in 1839 by English geologist Adam Sedgwick and the Scottish geologist Roderick Murchison.

The Devonian Period is often referred to the “Age of Fishes” because of the large amount of biodiversity of marine species that lived in Devonian seas.

During the Devonian Period the world's landmass was split into two supercontinents called Gondwana and Laurussia. At this time Devon lay under a shallow tropical sea.

These two Devonian supercontinents were situated relatively near to each other in a single hemisphere and were surrounded by the vast Rheic Ocean. Surrounding the supercontinents were subduction zones that would eventually collide setting in motion the formation of the single continent known as Pangea in the Permian.

Tropical Plymouth limestone fossil corals

A Devonian Period global climate was mild to tropical and this led to the ‘greening of land’ favouring the diversification, adaptation and radiation of plants across the supercontinents.

Plants increased the atmospheric oxygen levels and in turn helped the evolution of of terrestrial animals. The land was colonised by two main animal groups.

Firstly, the "tetrapod’s" meaning "four legs" in Greek. These were land-living vertebrates and secondly, the early terrestrial “arthropod’s”, including invertebrate wingless insects and the earliest arachnid’s millipedes, centipedes having an exoskeleton, a segmented body, and paired jointed appendages.

In the oceans, brachiopods, crinoids, echinoderms (including stemmed “blastoid” echinoderms), tabulate and rugose corals, ammonites, graptolites, and trilobites were widespread.

Tropical Plymouth limestone fossil corals

The most notable and diverse group of animals to evolve during the Devonian were the primitive fish.

The most formidable of them were the armoured Placoderms that first appeared in the Silurian with powerful jaws lined with bladelike plates that acted as teeth that fed on molluscs and predated on other fish.

The Devonian ancestors of fishes living today belonged to two main nonarmored groups.

The cartilaginous fish that later gave rise to sharks and rays.

The second group were the bony fish covered in scales and had manoeuvrable fins and gas-filled swim bladders for controlling their buoyancy. Most modern fishes are bony fish following the Permian-Triassic Extinction Event.

The transition from the Devonian Period to the Carboniferous Period is regarded as the second of the "big five" mass extinction events of Earth’s history. This was not a single event but rather two prolonged crises of species depletion known as the “Kellwasser Event” and “Hangeberg Event”. During these crises up to 70% of invertebrate species died though terrestrial plants and animals were largely unaffected.

Devon’s Devonian Geology

In south Devon the limestone, slates, sandstones and volcanic rock can be found dating back to the Devonian Period.

Devonian granite and limestone building stones

The sedimentary limestone was deposited during the Middle-Devonian when the seas were warm, shallow and abundant in life.

This limestone has always been used as a building stone. These limestones deposits are seen exposed at the Hoe, Cattewater and Mount Batten.

The limestone of south Devon is rich in well-defined fossils. Among the organisms that created the limestone in south Devon were sponge-like reef building organisms called Stromatoporids.

Stromatoporids had large calcareous skeletons that formed domes in excess of 5 meters in diameter. The stromatoporoid grew by secreting multiple calcareous sheets or laminae and the surface of the skeletons had raised structures called mamelons and canals called astrorhizae. These features are observed in many of the building materials in cross section and are graphically represented on the Geo Trail plaque's.

The Brewhouse Building showing fossilised coral

During the Devonian there was significant tectonic movement and mountain building called the “Variscan Orogeny”.

The impact of mountain building during the Devonian Period meant that the South West of England limestone became folded creating three distinct successions called the Plymouth Limestone, Brixham Limestone and Torquay Limestone.

It is the Plymouth Limestone succession that was quarried and used as building materials for the constriction of The Royal William Yard.

The Royal William Yard

Plymouth has always played a central role in Britain's maritime history particularly for the Royal Navy. The Royal Naval Dockyard, now Devonport, the largest naval base in Western Europe has supported the Royal Navy since 1691.

An integral dockyard service in Plymouth was victualling or the provisioning of warships at sea with dry stores and fresh produce principally sourced from the South West region.

During the 17th century the Secretary to the Admiralty, diarist and member of parliament Samuel Pepys PRS commented that sailors, love their “bellie above everything else”. This meant that the navy’s success in both battle and peacetime depended on the supply of food and drink.

The Mill Bakery at The Royal William Yard

Between 1825 – 1831 the 16-acre site of The Royal William Victualling Yard was built by the Victorian architect Sir John Rennie having been commissioned by the Commissioners of Victualling.

The Royal William Yard included a mill, bakery, brewery, slaughterhouse, cooperage and officers’ residents. The principle concern for The Royal William Yard was the hub for victualling of food & drink.

In 1992 the Royal Navy withdrew ownership and passed it onto the Plymouth Development Corporation. The Royal William Yard is still today considered to be one of the most important groups of historic military buildings in Britain, it is also the largest collection of Grade 1 listed military buildings in Europe.

The Royal William Yard Ferry

When you visit The Royal William Yard you will see that it has been regenerated. Where the once there was a working mill, bakery, brewery, slaughterhouse, cooperage and officers’ residents.

It has now been transformed into a premier business and lifestyle destination for restaurants, bars and a thriving commercial, retail, arts and cultural hub.

The Yard also has its own harbour with mooring facilities and regular ferry services connecting to the Barbican Landing Stage.

The Royal William Yard GeoTrail

I am not going to spoil your own experience by going into too much detail. The GeoTrail is an excellent way to spend an hour before either eating or drinking at one for the many fine restaurants and bars or before & after a business meeting.

You will certainly learn a small slice about the local Devonian Period geology and marine fossils in an engaging and interactive way and walkaway with a new appreciation or your surroundings. It will also drum up a thirst...

GeoTrail distinctive plaque #2

The GeoTrail has nine locations marked by a distinctive green and grey plaque. You can easily navigate to each plaque by using the What Three Words app or use the Yard Map on the free GeoTrail Guide.

On each plaque is a QR code that can be accessed by your mobile phone. Each QR codes directs you to a video explaining the features of each location.

Though I found the W3W app slightly clunky typing in the unique three word combination each time and being re-directed to Google navigation for guidance. It really did not detract from the experience.

The highlight of the GeoTrail were the videos by Dr Jodie Fisher who identifies where to look on the building and simply communicates the complex local earth science for non-geologists.

Highly recommended.