Boca do Inferno

The Boca do Inferno is a collapsed sea cave on the Atlantic cliffs two kilometres west of Cascais, near Lisbon: a chasm some thirty metres across where the swell drives in through a narrow opening and detonates against the rock. Its name is descriptive, and its documented history is stranger than the folklore usually attached to it. In 1896 it became the first cave ever filmed, by Henry Short for the British pioneer R. W. Paul. On 4 January 1929 the twenty-one-year-old poet Guilherme de Faria threw himself in. And in September 1930 the occultist Aleister Crowley faked his own death here with the help of Fernando Pessoa, leaving a note that Pessoa's journalist friend Augusto Ferreira Gomes duly found and duly wrote up. Crowley's own diary, thought lost until 2012, records him drafting the note two days before its stated date, boarding the Sud-Express, and reaching Berlin the day after the note was found, where he was reunited with the woman it said he could not live without.

The Boca do Inferno is a collapsed sea cave on the Atlantic cliffs about two kilometres west of Cascais, in the Sintra-Cascais Natural Park. Rainwater first dissolved fissures in the Lower Cretaceous marl and dolomitic limestone; the ocean then undercut the base until the cave roof fell in, leaving a chasm roughly thirty metres across with walls some twenty metres high, a surviving rock arch, and a narrow opening through which the swell drives in and detonates. The oldest descriptions explain the name by the sea. The Archivo Pittoresco of 1862 calls it a fearsome cave into which the sea enters "com estrondoso fragor, rugindo e refervendo lá dentro como se fôra na fabulada caldeira de Pero Botelho" — the cauldron of hell in the Portuguese saying. The Almanach das Artes e Letras for 1875 says that on stormy nights the rocks are wrapped in "longos uivos de agonia" and the glitter of spray, and that this is why "o povo deu-lhe o nome expressivo que o distingue". Its first wide fame came from a near-drowning. In October 1873 Queen Maria Pia, staying at Cascais, took her sons Carlos and Afonso, ten and eight, across the rocks to see the cavern on a gusty afternoon after a gale. A wave swept both boys into a cleft; the Queen went in after them and held them until António Silva, a keeper from the Guia lighthouse, lifted all three out. The Illustrated London News told the story on 25 October 1873 beside a sketch by Bordalo Pinheiro, and reported that the King had decorated Silva with the Order of the Tower and Sword. The 1875 almanac says the episode made the place "duplamente celebre". In 1896 the British film pioneer R. W. Paul sent his associate Henry Short to the Iberian Peninsula with a new lightweight camera. Among the films Short brought back was one shot at Cascais, catalogued by the BFI National Archive as "Sea Cave Near Lisbon", showing the waves breaking at the mouth of the Boca do Inferno. It is a matter of seconds long, it survives, and it can be watched free on the BFI Player. It is generally described as the first cave ever committed to moving pictures. The site's association with death is also documented, and it is earlier than the story usually told about it. On 4 January 1929 the poet Guilherme de Faria, born in Guimaraes on 6 October 1907 and the author of seven slim books before he was twenty-two, threw himself into the sea here. He was twenty-one. Death had been attached to the name for some years by then: on 11 June 1923 a Portuguese feature in eight acts directed by Ernesto de Albuquerque, O Suicida da Boca do Inferno, opened at the Salão Foz and the Chiado Terrasse in Lisbon. When Fernando Pessoa's detective narrator writes, a year and a half after Faria's death, that "many suicides have of course taken place there" and that the place "is an accepted suicidal region", he is describing a reputation that already existed. What happened in September 1930 was a hoax, staged by two named men, and almost every step of it is on paper. Aleister Crowley landed at Lisbon on the liner Alcantara on 2 September 1930 with his lover Hanni Larissa Jaeger, a German-American woman who turned twenty two days later. Pessoa met them at the quay. Crowley's diary for that day reads: "Tied up in Lisbon 3.45. Pessoa met us: a very nice man. Hotel de l'Europe." The diary for that month was long thought lost; a typescript copy surfaced and was published in 2012 by Marco Pasi in the journal Pessoa Plural, and it lets the trip be followed almost day by day. On 12 September Crowley walked out to the site and was unimpressed: "Walked to Cascaes and Boca do Infierno. I wish the W[est] coast of Scotland could see it: it hasn't had a good laugh for a long while." The relationship with Jaeger was collapsing. She went missing on 17 September, came back on the 19th, and on Saturday 20 September sailed for Bremen. Crowley's entry is four words of programme: "She left by Lloyd Bremen - And I get on with the Job." On Sunday 21 September, from Sintra, he wrote in the diary: "Developed plan to utilize local scenery - see 12 Sept[ember]." Immediately below, he copied out the text of the note he had just written, in English: "I cannot live without you. The other 'Boca do Infierno' will get me - it will not be as hot as yours." It is signed with the name of Tu Li Yu, a Chinese sage Crowley claimed to have been in a former life. The note was dated not by the calendar but in Thelemic and astrological form - Anno XIV, Sun in Libra - which fixes it to after 6.36 p.m. on 23 September. On 23 September Crowley took the 11.30 Sud-Express out of Lisbon: "Shall I risk Sud-Express? ... I think I ought to do it. (I did)." He was at Hendaye on the 24th and dining at Laperouse in Paris that evening; at Aachen at 7 a.m. on the 25th, with 700 francs left and, in his own words, the "problem: to reach Berlin at 6.10 to-night". That same afternoon - 25 September, in the late hours of the day - Augusto Ferreira Gomes, a journalist and sub-editor of the illustrated weekly O Noticias Ilustrado and a close friend of Pessoa, "found" the note. It lay in an ungummed envelope addressed to Miss Hanni L. Jaeger and marked "Please forward", weighed down by an empty cigarette case decorated with Egyptian figures, on the lip not of the Boca do Inferno itself but of the adjoining cleft, a narrower and far deadlier fissure known as Mata-Caes - "kill-dogs" - which, unlike the chasm proper, never returns a body. The envelope and paper carried the letterhead of the Hotel de l'Europe in Lisbon. Gomes took the find to the Diario de Noticias. The press censors held the item back; it appeared on 27 September. That afternoon Gomes handed the objects to the Criminal Investigation Police, before its interim director Dr. Alexandrino de Albuquerque. Pessoa arrived shortly afterwards and identified the cigarette case as one he had seen in Crowley's hands, and the handwriting as unmistakably his. He then argued to the police that the letter's astrological date was trustworthy because, as he put it, no astrologer ever misdates a letter in the symbols of the stars - an argument that survives in his own manuscript, and that his friend's diary quietly contradicts, since the text had been drafted on the 21st. While Lisbon debated whether the English magician had drowned for love, Crowley was in Berlin. On 26 September he called at the American Express office, left a note, and was reunited with Hanni Jaeger the same day: "She came to the flat at 2." The woman he could not live without had been with him again for less than twenty-four hours after the note was found. Gomes then wrote the story up himself, with photographs, in O Noticias Ilustrado of Sunday 5 October 1930; the Paris weekly Detective carried it on 30 October. Pessoa, meanwhile, began drafting a detective novel about the investigation he had helped make necessary - hundreds of pages of English typescript narrated by an imaginary English private investigator, with a preface datelined "Barcelona, Dec. 1930". He never finished it. It remained in his archive and was published by Tinta-da-China in 2019, edited by Steffen Dix, together with the Crowley correspondence, under the title the case had acquired in the newspapers: O Misterio da Boca do Inferno.

Checked August 2026. The Boca do Inferno is a free, unenclosed, open-air viewpoint on the coast road west of Cascais - Avenida Rei Humberto II de Italia, 2750-642 Cascais - inside the Sintra-Cascais Natural Park, classified since 1994. There is no gate, no ticket office and no opening hours: the site is simply there, day and night. Railings and stepped walkways run along the landward rim, with a lower terrace closer to the arch. Getting there is easy and is best done on foot. Cascais is the terminus of the suburban railway from Lisbon's Cais do Sodre - the same line Pessoa's narrator describes in 1930, when he put the distance at eighteen miles - and the chasm lies about two kilometres west of the town centre, a walk of roughly half an hour along the seafront promenade and the coastal path, or a short ride by bicycle. There is free parking nearby, and kiosks and craft stalls at the entrance. The viewpoint itself is level and reachable by wheelchair, though the lower rocks are not. The small white plaque fixed to the rock, which carries a Portuguese version of Crowley's note, is the only interpretation on site; nothing there mentions Guilherme de Faria, and nothing marks Mata-Caes, the narrower cleft alongside the chasm where the letter was actually left. Take the danger seriously. This is not a decorative hazard. The rock beyond the railings is fractured, wet and undercut, and the Atlantic here produces sudden surges that reach far above the apparent waterline; the National Maritime Authority and the municipality post bilingual warning and no-access signs for that reason, and people who cross the barriers and have to be rescued can be fined up to two thousand euros. Deaths and serious injuries recur: on 16 April 2022 a young man died and another was left in a critical condition after a fall here, and rescues of visitors who stepped or backed over the edge - in one 2019 case, a tourist retreating to frame a photograph - are reported regularly in the Portuguese press. The practical rules are the obvious ones and they are enough: stay behind the railings, do not climb down to the lower rocks, never turn your back on the sea to pose for a photograph, and keep well away entirely in heavy swell or storm conditions, which is precisely when the place is at its most spectacular and most lethal.