If you are looking for a stroll in Lisboa away from the tourists but with views of the 25 de Abril Bridge and Cristo-Rei then the Águas Livres Aqueduct might just be what you are after. In fact if you arrived in Lisboa by plane or train then you are probably already pondering if you can walk across this remarkable example of 18th century engineering. Well the answer is a resounding yes!

The Águas Livres Aqueduct has 35 arches and stands high above the Alcântara Valley in the south west of Lisboa. It was once part of an 58kmile water network, and amazingly was in operational use for over 200 years from 1748 until 1967. It also survived the great earthquake of 1755.

It has one of the tallest stone arches in the world. Surprisingly it is very difficult to determine which is the tallest stone arch. There are lots of articles and posts about the longest spans, and much also to be found on ancient aqueducts and natural arches but very little on heights of man-made stone arches, and even less on this incredible piece of Portuguese engineering. However the research MrB and I have done to date would suggest that its own website is correct at describing it as having the ‘largest stone arch of this type in the world at 65.29 m high and 28.86 m wide.

The views from its two walkways are stupendous even on grey cloudy days but it was the view inside that really caught my imagination. It felt like an infinity mirror except this endless view is real.

The walkways were used as a point of entry to Lisboa until the mid 19th century by washerwomen, market traders and others from rural areas in the south and west of Lisboa. The reason given for their closure is that they had become the haunt of one of Europe’s worst serial killers Diogo Alves. However I’m not sure how true that is as they closed in 1853 and the Diogo Alves was caught in 1840. What is true though is the horror of Diogo Alves crimes. Over a period of at least three years he threw his victims off the highest point of the aqueduct after robbing them as they crossed the walkways at night. Many of his early victims were thought at the time of their death to have died by suicide rather than murder, however when he was finally caught it was realised they were murdered. It is believed he murdered at least 70 people. The exact number is unknown, and it is also unclear when he was part of a gang who committed these murders. He was finally caught in 1840 after murdering a doctor and his family, and was sentenced to the gallows in 1841. Bizarrely his head was preserved as the Medical School in Lisboa wished to study it to try and determine what lead him to do what he did! Don’t think it helped them, but his head still exists and can be found in a jar of formalin at University of Lisbon.

If you want to walk it yourself then it is quite safe these days! It is open Tuesdays thru Saturdays from 10 am to 5:30 pm. The entrance on Calçada da Quintinha is about a 20minute walk from the upper end of Parque Eduardo VII. Alternatively you can take a short walk from Amoreiras bus-stop after catching the 711  bus from Restauradores.

The Aqueduct is managed by Lisboa’s water company and as well as the aqueduct they also manage four other museum sites including underground reservoirs, tunnels and a pumping station. Perfect day out for those who enjoy engineering and for those who prefer to discover something rather different in Lisboa.  If however you are more of an armchair explorer then you may prefer to visit the lovely Jo and her Monday walkers for less gruesome walks around the world.