2,400-Year-Old Esparto Sandals Reveal Roman Mining Secrets in Spain

A recent archaeological investigation in southwestern Spain has uncovered an astonishingly well-preserved collection of esparto grass sandals. Discovered in the ancient mining settlement of Urium, modern-day Riotinto, these eight sandal soles reveal that the same style of footwear was worn by miners continuously for over 400 years, spanning from the Iron Age through the Roman period. The remarkable preservation of these organic materials offers a rare glimpse into the daily lives and material culture of ancient workers.

The research, led by a team from the University of Granada and published in the journal Pyrenae, examined the soles recovered from the Nuevo Filón Norte 1 sector of the Riotinto mining district. These artifacts were found buried within two large accumulations of ash, which were the result of cleaning metallurgical furnaces. The dry, alkaline environment created by the ash was crucial in preventing the decay of the plant fibers, allowing these delicate objects to survive for more than two millennia.

A Tradition of Craftsmanship

Radiocarbon dating of three of the sandals revealed a broad chronological span. The oldest piece dates back to between the 4th and 2nd centuries BC, another to the 2nd and 1st centuries BC, and the most recent to the 1st century AD. This extensive timeline demonstrates that the use of these esparto sandals was not a fleeting trend but a deeply rooted tradition that persisted despite the profound cultural and political shifts brought about by Romanization in Hispania.

2,400-year-old esparto grass sandals. (University of Granada)

The sandals were crafted from Stipa tenacissima, a tough and flexible esparto grass abundant in the Iberian Peninsula. Researchers utilized advanced techniques, including scanning electron microscopy and X-ray micro-computed tomography, to analyze the braiding patterns without damaging the fragile remains. The analysis highlighted the artisans’ advanced technical knowledge; thicker cords were strategically placed in areas bearing the most weight, while finer fibers were used for straps and binding.

Practical Footwear for Harsh Environments

The continuous use of this specific footwear design underscores its practical utility in the demanding environment of the ancient mines. The esparto sandals provided essential grip and protection for workers navigating the rough and often slippery terrain. The researchers link these artifacts to the solea spartae mentioned in ancient Latin texts—a type of simple, inexpensive footwear favored for its effectiveness in such conditions.

Evidence of heavy wear on the forefoot and heel areas of the soles suggests prolonged use. Furthermore, the absence of the upper cords that would have secured the sandals to the feet indicates that they were discarded only when they were completely worn out and beyond repair. This reinforces the notion that these were functional work tools rather than luxury items.

Expanding Our Understanding of Ancient Mining

Alongside the sandals, the excavations yielded other esparto objects, including ropes and baskets, all preserved by the same fortuitous ash deposits. These findings collectively provide a much clearer picture of the material culture and daily lives of the people who labored in one of ancient Hispania’s most significant mining centers.

The Riotinto collection now stands as one of the largest assemblages of Roman-era plant fiber footwear in the Iberian Peninsula. By studying these rare organic artifacts, researchers are filling significant gaps in the archaeological record, highlighting the vital role of plant fibers in the ancient domestic economy and the enduring resilience of indigenous craftsmanship under Roman rule.

Top image: 2,400-year-old esparto grass sandals show Iron Age miners used the same footwear for 400 years Source: University of Granada