This excerpt of Ferdinand Gregorovius' book Wanderjahre in Italien describes how he visited the caves of Capri.
Between the Faraglioni and the small marina, one of the most spacious grottos on this seashore, so rich in cave formations, arches over limestone blocks. It is called "La grotta dell' arsenale". The water does not cover it, it is an earth cave. Roman masonry still clings to its walls, and there are also traces of chambers. Now, the name of the cave probably teaches us that it was once a storehouse for the navy, if not also a shipyard for the galleys of Tiberius, for it is high enough, and at its entrance we can also see some traces of the iron that worked the rock. The place is called "L'unghia marina". Some remains of old walls can be seen here, on the stony shore as well as on the heights. Ancient buildings can also be seen at Cape Tragara, around which the Faraglioni and the Monacone cliff stand in the water. There was probably a small port here at the time of Tiberius. Perhaps a covered passageway led from the villa of Mount Tuoro above to the port, where galleys prepared for emergencies lay. For even on this island floe the tyrant hovered in constant fear and had taken every precaution to ensure that he could escape seawards at any time.
The near east coast of the island rises to the height of 970 feet and plunges perpendicularly into the sea, so that on the highest edge of the shore is the villa of Zeus. Here the whole shore is of fearsome wildness. If you first go from the Tuoro grande through the small valley of Matromania to the south-eastern side, you come to a place where the shore contracts at an angle of the steepest lines. There, one looks into a fantastic forest of rocky prongs that stare around the shore in ghastly confusion. In the middle of it, a rock opens up into the most magnificent arch, the Arco naturale. Next to the Blue Grotto, it is the most surprising single feature of the island. Deep down the sea, shaded in black, high up the sky, red-brown cliffs all around, above the sea the magical sight of the Cape of Minerva and the coastal mountains of Amalfi and Salerno.
Here a rugged stairway leads down, where in the middle of the shore a deep, in the middle of the shore, the mysterious Matromania. It is about 55 feet wide and 100 feet deep, a work of nature, but it was enlarged by human hands; Roman masonry can already be seen at the entrance, and masonry still hangs on the walls inside. In the depths, two masonry walls rise in a semicircle, one above the other like seats; steps led through the middle, probably to the niche of the god whose image column was erected here. Everything suggests that we are looking at the cell of a temple.
The name Matromania, which the grotto bears, and which the people in unconscious irony have twisted into Matrimonio, as if Tiberius had performed his weddings here, is explained from "Magnae Matris Antrum" or from "Magnum Mithrae Antrum". This sanctuary was dedicated to Mithras, for one of those countless reliefs depicting the Mithras sacrifice was found in the grotto. In the studies at Naples I saw two of these representations; one relief was found in the grotto of Posilip, the other in the Matromania. They depict Mithras in Persian costume, kneeling on the bull, into whose neck he thrusts the sacrificial knife, while snake, scorpion and dog wound the bull. This grotto of Capri was well suited for mystical sun worship; it faces east, and whoever sees Helios rising from its depths and gazes at the purple glow of the mountains and the sea, truly becomes a sun worshipper here.
In this cave a mysterious find was made, a marble tablet with a Greek funerary inscription, which reads thus:
You who inhabit the Stygian land, you good demons,
Receive me too now, take the wretched one to Hades,
Whom Moira's command did not carry away, the sovereign power only
With death suddenly struck, when blameless I never knew.
A moment ago Caesar heaped upon me many a gift,
But now he has destroyed hope for me and my parents.
I have not yet reached fifteen, not twenty of the years,
Alas! and I no longer see the light of the enlightening day.
Hypatos am I called; to thee do I yet call, my brother,
Parents, I beseech you, O weep no longer, poor ye!
Of what terrible deed does this epitaph of a boy speak in such mysterious words? Here is implied a novel of Capri. Poor Hypato's lot is lost, but I know it. In a demonic hour Tiberius sacrificed his favourite boy to the sun, here in this cave, here before this cell. So later Hadrian sacrificed the beautiful Antinous to the Nile. In those days human sacrifices, though not frequent, were still in custom, and were most commonly offered to Mithras.
Yes, if this cave could open its mouth and these rigid cliffs would begin to speak, they would have gruesome fables of antiquity to tell.
Few Tiberian ruins are to be found in Ana-Capri; the vintner has erased them, and there were fewer buildings here than on Capri. Most of the remains of antiquities are to be found on the Damecuta plain, a fertile land that slopes gently down to the coast and on whose banks lies the Blue Grotto. It is peculiar that Upper Capri, in spite of its height, has a lower coast than Lower Capri; for the high mountain descends long into the sea to the west as well as to the north, but yet the shore is neither accessible to boats nor to human feet, shoreless, harbourless, and bringing certain ruin to the shipwrecked.
The tower of Damecuta marks the approximate location of the now world-famous Blue Grotto, the wonder of Capri, but not the only one of this Sirenian island. My host Michele tells me in detail about the day it was discovered. He took part in the venture as a boy. It was his late father Giuseppe, August Kopisch, the painter Fries and the skipper Angelo Ferraro who dared to enter this grotto. All of them are now dead, only Michele knows of the discovery. An uncle of Pagano, a priest on Capri, warned the company to refrain from the attempt, for the cave was the abode of evil spirits, and many sea monsters dwelt there. It was also difficult to enter because there was not a single small barque on the island before the discovery. So Angelo penetrated on a tub, and Kopisch and Fries swam. My host vividly described to me the exultation of both painters when they were in the grotto, and especially, he says, Fries was as if out of his mind, he swam out soon, and then in, and always with cheers and whoops. August Kopisch had no peace, he immediately hurried to Naples and fetched his friends, and so he did from time to time. Pagano kept an old tourist book like a relic; in it Kopisch wrote the following deed of discovery under 17 August 1826:
"I would like to draw the attention of friends of wonderful natural beauties to a grotto that I discovered with him and Mr. Fries, according to the information of our host Giuseppe Pagano, and which, due to terrible superstition, people have not dared to visit for centuries. Until now, it has only been accessible to good swimmers; when the sea is calm, it is possible to enter in a small boat, but this is dangerous because the slightest rising air would make it impossible to get out again. We named this grotto the blue one ("la grotta azzurra") because the light from the depths of the sea illuminates its wide space in blue. You will find yourself strangely surprised to see the water filling the grotto like blue fire; every wave seems a flame. In the background, an old path leads into the rock, perhaps to Damecuta above, where, according to legend, Tiber locked up girls, and it is possible that this cave was his secret landing place. So far, only a marinaro and a donkey driver have been so hearty as to venture on this venture, because all kinds of fables are circulating about this cave. I would advise everyone, however, to make an agreement with these two beforehand, because of the price. The innkeeper, whom I recommend because of his knowledge of the island, wants to have a very small, narrow boat built, which would then be easier to enter. For the time being, I only recommend it to good swimmers. It is most beautiful in the morning, because in the afternoon the daylight falls in more strongly and more disturbingly, and the wonderful magic is thereby diminished. The picturesque impression is increased if one swims in, as we did, with flaming pitch-pans."
The excellent Kopisch has discovered a magnificent monument for himself on this island, and I feel as if the wonderful grotto were German property and a German symbol. At this point, many memories of Tieck, Novalis, Fouqué, Arnim, Brentano, all of whom have now gone home, except for Eichendorff and Heine, the last enchanted prince of this school of poets, are interwoven with this poet-painter. Let us then pour a consecration out of the blue firewater of Capri onto the graves of those dead poets. For they all dreamed of this grotto, and truly the prize of its discovery could only go to a painter and poet from the time of those who sought the blue miracle flower of poetry among the Undines in the depths, among the Lady Venus in the mountain and in the subterranean grottoes of Isis. They were all amiable little and big children, boys with the wonder horn. Their high priest Novalis looks like a beautiful, pale boy who has put on the long preacher's robe of his dead great-grandfather and speaks mystical wisdom, of which no one knows how the child came by it. Her muse, however, is a siren. She lives in the Blue Grotto on Capri, the island of the cruel voluptuary Tiberius. They have all heard her heart-stirring song and none have found her, they have all sought her and died of longing for the blue miracle flower. Goethe prophesied it to them in the "Fisherman": "Half she drew him, half he sank down and was seen no more." And now that the blue miracle flower, namely the blue miracle grotto, for that was the unknown mystery, has been found, the spell has been broken, and no song of the Romantics will be heard again in German lands.
When I entered the grotto, it was as if I had returned to one of those fairy tales into which one lives as a child. World and day have suddenly disappeared, and there one is in the arching earth and in a twilight of blue firelight. The waves breathe still and sparkles rise up as if flashing emeralds and red rubies and a thousand carbuncles sprouted from the depths. The walls are ghostly blue and mysterious to behold, like the palaces of fairies. It is the glow of a strange being and a strange spirit, wonderful, secret and eerie at the same time. Everything is silent as in a shadow world, because no one even likes to talk. You exult at first, then you are silent, and only the rippling oars or the giggle of the waves that wrap phosphorus wreaths around the rock walls resound. The blue magic water beckons irresistibly. You have to jump down, and you plunge as if into a sea of light.
Yes, I believe that Tiberius bathed here and swam among the beautiful girls of his harem, as Suetonius tells us. In this voluptuously flowing flood of phosphorus, the girls' bodies glowed like the radiant bodies of sea fairies, and there was no lack of siren song and flute playing here to turn such a bath into an unspeakable game of lust. I saw a siren painted on a Greek vase, a marvellous creature that raises both lily-white arms, giggles, and strikes two flashing ore basins together. So here the sirens come up out of the blue blaze, strike the ore basins together, giggle and emerge and submerge. But only Sunday people see them and little children.
One must marvel at this island's wealth of grottos. Earth caves and sea caves, strangely shaped and all beautiful, there are so many here that it is impossible to get to know them all. I have entered more than fifteen of these caves and have found a small one on the southern side, which shows exactly the blue light effects of the "Grotta azzurra". In others there are green lights, depending on the nature of the ground, In others, depending on the nature of the ground, green lights phosphoresce in whitish fire, especially in the "Grotta verde", the most magnificent of Capri, with its splendid vaulted architecture and the enclosure of grandiose rock pinnacles. It is not entirely covered underground, but has a rock passage from one side to the other.
Some of these caves have names, like the Marmolata, the Marinella, others are nameless. I took the pleasure of naming all the nameless ones I visited, without claiming the glory of a cave explorer. And so I alone know how beautiful it is in the grotto "Stella di Mare", in the sea-flower adorned grotto "Euphorion", in the grotto of the sea spider, whose walls are yellow and whose rock, where it wets the wave, shimmers rosy, velvety green and whitish. In one grotto there was a slurping of the waves and an anapaestic crashing of the waves, so that I consecrated it to the Eumenides. All of them lie from the banks of the Solaro to beyond the Faraglioni, inconspicuous on the outside, since their mouths often escape the superficial glance, inside they are high-domed, dark, waveless, inhabited by sea spiders, sea urchins, sea stars, a magical hermitage of ghosts.
It is most rewarding to circumnavigate the entire island. It takes three hours to do so and you can also visit some caves in that time. The west coast does not have the cave formation, because here the shore of the Solaro sinks down between the two capes Punta di Vitareto and Punta dei Carena. It sends out three low but rugged peaks, Campetiello, Pino and Orica, which are fortified with entrenchments. And this was also the place where the Muratists climbed the rocks at night. But if you row around the Carena, the southern shore suddenly becomes terrifyingly high and steep; the gigantic cliffs rise vertically from the water level to the clouds that surround their summits. The south coast continues in this way as far as Punta Tragara, and no less sublime, bizarre and wild at the same time is the whole east coast as far as Lo Capo, the north-east cape of the island. Here the shore is full of stalactite cave formations.