Los Milagros aqueduct

It is not called «de los Milagros» — of the Miracles — for any religious wonder: the name comes from local amazement that such a mass should still be standing century after century, to the point of taking it for a miracle.

The name was literal, and it was counted one by one: each pier was called «a miracle». Bernabé Moreno de Vargas records it in his History of the city of Mérida (1633), adding that people credited the work to the emperor Trajan.

Antonio Ponz, in his Viage de España (1784), left the count done: thirty-seven piers standing, «los Milagros». It is the oldest surviving census of the monument.

There are phalluses carved into the ashlars. Four have been identified: a double one — two erect penises joined — on the south face of the eighth pier on the right bank of the Albarregas, and three single ones, horizontal with the glans pointing right, on the fifteenth, sixteenth and eighteenth piers on the left bank.

They were not a stonemason's joke: the phallus, the Roman fascinus, was also set in streets, floors and public works as a charm for the community, to keep the evil eye out of Emerita Augusta and draw in prosperity at the same time.

In the 18th century a whole «miracle» was pulled down to reuse its stone in rebuilding the hermitage of the Santísima Trinidad: time did not take it, it was dismantled to build something else.

That the water came from Proserpina, as every guidebook repeats, is under dispute. Santiago Feijóo, of the Consorcio de la Ciudad Monumental, has traced remains of the conduit beyond the dam and argues that the original height of the dam wall does not reach that of the aqueduct: the two cannot have worked together.

On that reading, the aqueduct was built to bring clean water from local springs, and Mérida's two dams would be far later — Visigothic or Islamic — raised when the Roman conduits had already been abandoned, to drive mills, water livestock or wash wool.

In 2019 a study presented at the Universidad Autónoma de Madrid concluded that the aqueduct was not Roman but Visigothic, and the city rounded on it: the dating rested on the thermoluminescence of a single brick, which gave the year 290 with a margin of error of ±106 years.

The arguments against are stratigraphic: there is a 1st-century mausoleum built against the aqueduct — which therefore already existed — and the channel is found silted up in the 4th and 5th centuries, exactly when the study claimed it was being built.

It is impressive from outside, but the water had very little room: the specus, the channel, was only some 56 cm wide, lined with opus signinum. Twenty-five metres of masonry for a narrow spout.

A Visigothic-period repair has been identified on one of the piers, between the settling tank and the Albarregas crossing: somebody went on maintaining it when the Empire was no longer there.

The stork nests up top are not light: a new one weighs between 50 and 100 kg, over the years it reaches 250, and the record on file is 500 kg. On top of a two-thousand-year-old Roman arcade, that is an engineering problem.

So in 1991 local ornithologists put up five artificial nests of vine shoots in deliberately chosen spots: on the piers, never on the brick arches, which are the weakest part of the conduit. That same year five chicks fledged.

The colony is shrinking: in 2024 only four pairs bred, and several nests disappeared during maintenance work on the aqueduct.

Alternating courses of granite and red brick was not only structural: that two-colour play has been pointed to as one of the sources of Hispano-Muslim caliphal art.