Eight remains of sandals woven from grass thrown into a garbage heap more than 2,000 years ago are new and precious finds for a team of archaeologists in Spain. Thanks to its exceptionally well-preserved conditions, researchers are now learning more about Iron Age life in the Iberian Peninsula at the cusp of the Roman Empire’s arrival in the region.

The footwear is documented in a study recently published in the journal. Pyreneesand come from excavations at Urium, an ancient mining settlement located in southwestern Spain, about 55 miles west of Seville. Archaeologists found the shoes near a complex of metallurgical workshops dating to the mid-1st century BC. During its operations, the extensive site encompassed four work areas, 10 furnaces and 16 other rooms with as-yet-unknown purposes. The team did not locate the sandals in the workshop itself, but within the ash deposits in the adjacent courtyard. Based on additional scattered discards, such as oven remains and everyday items, these likely served as general trash heaps.

The soles of the sandals are made of a resistant grass called esparto (Stipa tenacissima), with striated textures and groupings of parallel fibers that differentiate them from other textile plants such as hemp and linen. Most esparto grass was used raw rather than softened through multiple soaking cycles, and artisans wove it into flat, narrow braids which were then shaped into soles. A combination of thick wires and thinner strands were also carefully arranged depending on their uses. The thicker laces formed the weight-bearing parts of the shoe, while the more flexible cords formed the joints and ties. Each sole measured between 6.7 and 9.8 inches long, and at least four of them were clearly for the left foot.

They were not new sandals abandoned or lost by their owners. Instead, signs of heavy use match where archaeologists found them. Most of them were missing the laces holding their feet together when they landed in the trash, while damage to the forefoot sections showed long-term wear.

The age ranges also especially surprised the researchers. Radiocarbon dating traced one sole to the early Roman period (around 28-124 AD), while another example was built during the Late Iron Age (360-205 BC). The dating of a third sandal produced a broader time window, around 175-56 BC. C. This implies that Urium was home to local workers repeatedly for almost 500 years. That said, the two oldest artifacts could have originated from earlier deposits that Roman residents subsequently disturbed or discarded. Regardless, the esparto sandal style was clearly used for decades before the Romans completely absorbed the area in 19 BC.

Plant-based footwear typically decomposes quickly, leaving little for archaeologists to study. But thanks to the soles of sandals that remained among the piles of furnace ash for centuries, they remained comparatively stabilized. Organic preservation also preserved ropes and baskets made of similar materials found by researchers in the sediment.

From their condition at the time of their disposal, it is clear that these esparto sandals were not casual accessories, components of ceremonial costumes, or luxury items. Instead, their worn condition, broken straps and muddy soles show the workers’ preferred footwear. It is rare for the remains of such ancient people to endure for millennia, and it is even rarer for items made from such short-lived organic resources.

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