Excavations at Cockenzie Harbour have uncovered exciting new insights into the salt industry and Scotland’s earliest railway.

Last month, archaeologists and volunteers from 1722 Waggonway Project were hard at work to learn more about the history of the area.

The team focused on an area at the north-east corner of the harbour, where previous archaeological digs had revealed surviving elements of the panning industry.

After four days of intense digging, the team found that the complete footprint of the salt pan house had survived, with the internal workings of a furnace still in situ – including a brick furnace, ash pits and curved chimney flues.

The volunteers also found two cast-iron pan supports, known as taplins – only the third discovery in Scotland of the items.

To top it off, the team realised that the design of the furnace mirrored that of 18th-century scientist William Brownrigg as set out in his 1748 book The Art Of Making Common Salt.

Through its construction, the furnace has been dated to about 1785, leading project researchers to conclude that the salt pans at Cockenzie were upgraded by the Cadell family of industrialists shortly after their acquisition of the assets in 1779.

Alan Braby, lead archaeologist, said: “The salt pan archaeology is amazing.

“Brownrigg’s book shows a schematic of an ideal 18th-century salt pan house and we have found an identical layout in this building.

“This is a quite remarkable dovetailing of evidence from both the documentary sources and the archaeology in the ground.”

Alongside the salt pan, archaeologists and volunteers uncovered previously unseen sections of the waggonway that brought coal from Tranent for the salt pan furnaces.

A double row of stone sleeper blocks, large stones used to support the iron rails, some with in situ iron chairs, were found, revealing new insights into railway construction in the early 19th century.

Anthony Dawson, railway historian and archaeologist, said: “The four days of archaeology has considerably furthered our understanding of how railways built with stone blocks and cast-iron rails were built, maintained and worked.

“The excavation revealed a 10m-long stretch of track with exceptionally good preservation – not only were there traces of the iron rails found, but three beautifully preserved cast-iron rail chairs were found in situ on their stone sleepers.”

The discoveries came in a four-day event as part of East Lothian Council’s Archaeology and Heritage Fortnight, with about 500 people visiting the team on site.

Ed Bethune, chair of the Waggonway Project, declared the event a “resounding success” and was delighted it had provided a huge insight into the area’s rich history.

He said: “We have taken the knowledge of the salt pans and waggonway to the next level, adding significant information to the archaeological record and giving fresh insight to some key areas of industrial history.

“To gain such unique and important information from the excavations is quite incredible, and we’re confident that post-excavation research will reveal yet more fascinating information about these important industries.”

The Waggonway Project’s excavations were supported by East Lothian Council, CFA Archaeology, Wessex Archaeology, Dig It!, Sea Green Wind Energy, Salt of the Earth Heritage Connections and Cockenzie Regeneration.