A submerged Roman-era city near the equator off East Africa’s coast? A document written in about CE 40 by a sea merchant confirms its existence: “The very last port of trade on the coast of Azania, called Rhapta where there are great quantities of ivory and tortoiseshell.”
He lived in Egypt and in about CE 40 wrote the Periplus of the Erythraean Sea, a coastal log of what is now called the Indian Ocean.
Rhapta was also included in Claudius Ptolemy’s monumental Geography, an epistle on how to make maps completed in about 150 CE. He listed 6 500 locations known to the Roman world, including Rhapta, which, tantalisingly, he called a metropolis.
Rhapta was the southern extent of the trading reach of the Roman Empire, one of two legs which traversed the Indian Ocean from the Red Sea, the other as far as the Ganges off eastern India. Both routes used the monsoon winds, which blow one way for part of the year, then switch and blow in reverse.
Researchers have been looking for Rhapta for decades. The Periplus captain said it was about two runs (185km) beyond Menuthias. The problem, though, is that Menuthias could be either Pemba or Zanzibar, both off the mainland and about 100km apart.
Lionel Casson, in the Periplus Maris Erythraei, the defining work on the Periplus, said that if it was Pemba, then Rhapta lay in the vicinity of today’s Dar es Salaam; if it was Zanzibar, then the metropolis was at the mouth of the Rufiji River, more or less opposite Mafia Island, 133km south of Zanzibar.
The Swahili coast has been extensively excavated by archaeologists, in recent times by Felix Chami, professor of archaeology at the University of Dar es Salaam. I spent an hour with him at the university, he generously sharing his research insights which show settlement patterns reaching back to neolithic times, Iron Age settlements 2000 years ago and trade items from Roman and later empires.
Chami said the doyen of East African coastal archaeology, Neville Chittick, was convinced Rhapta was in the area of the Rufiji River. Shortly before his death in the 1980s though, Chittick said it was possible all traces of Rhapta had been washed away or buried.
Then in April 2016, Alan Sutton, a South African diver living in Tanzania, told in a web report of an unusual discovery he made during a helicopter trip off the usual flight path to Mafia. The tide was low, a large rectangular structure revealed itself.
“Geologically speaking, Mafia Island is a sand island. There are no rocks in the area. Neither are there barrier reefs and the formation appeared highly unusual,” wrote Sutton.
“On a previous trip in 2001, by boat, we saw reef in the water and stopped. The visibility was very poor. I put my head into the water and saw reef with little growth on it, but it looked to me like a wall.
“We decided to visit. After several unsuccessful attempts due to low water visibility, we found the formations on a spring low tide.
“What we found was far larger than expected. A series of what appear to be wide foundations ring a large area. Along the entire perimeter created by these foundations, many thousands of square and oblong blocks lie to either side. Some — as large as five square metres and 40cm thick — have fallen off the foundation and others are still leaning against it.
“The north foundation, which runs roughly west-east, is approximately 3.7 kilometres long, using GPS. There may be parts covered by sand however, so it could be longer. The width between the north and south foundations at the widest point is approximately one kilometre. The foundations vary in width from 10 metres to 20 metres.
“The south foundation is mainly underwater and is equal in length to the north foundation.”
Sutton’s conclusion: “The site is very large, certainly the size of a city, is definitely manmade and very old. There appear to be other formations partially covered by sand in the area between the outer walls. There is a circular structure seven metres wide off to the side of one of the walls but we have not sited it ourselves. Other than the blocks and the foundations no other items were seen.
“The blocks appear to be made out of a type of matrix light brown in colour which resembles sandstone. Given the sheer number and assumed weight of the blocks, they are likely to be made of some type of cement.
“Some blocks also have small perfectly square holes in them as well as oblong holes near the edges. There are no sandstone deposits known in the area. The logistics of transporting the blocks to the area would have been formidable.”
Sutton estimated, based on the age of the porites corals, that it had been under water for at least 550 years, and speculated it may have destroyed by a tsunami.
Surprisingly, since the search for Rhapta goes back decades, Sutton’s find is clearly visible on Google Earth. But then Google Earth has only been available to researchers relatively recently.
Sutton told Felix Chami about his find. The Dar Post reported in April 2016 that Chami said the mysterious ruins could date back to the time of the Roman Empire — and might even be the ancient city of Rhapta.
“It wouldn’t surprise me if it is a Roman structure. Rhapta was in this area without a doubt,” said Chami. Evidence of Roman-era activity has already been found both in the Rufiji Delta and on Mafia Island, the Dar Post said.
Chami told me: “Ptolemy put Rhapta at 8 degrees latitude, which is Mafia and the Rufiji Delta. He also mentions one of the islands of Azania as Mafiaco, which is probably Mafia. He noted that people at Rhapta were known as Rafiji, which is very close to the Rufiji people today known as Warufiji.”
Assuming Sutton’s discovery is the ruin of Rhapta, his account is one of just two first-hand accounts, the other coming from the Periplus captain: “Very big-bodied men, tillers of the soil, inhabit the region; these behave, each in his own place, just like chiefs.
“The principal imports into these ports of trade are: spears from Muza [a port in now Yemen] of local workmanship; axes; knives; small awls; numerous types of glass stones … the area exports: a great amount of ivory but inferior to that from Andulis [a port on the Egyptian side of the Red Sea]; rhinoceros horn; best-quality tortoise shell after the Indian; a little nautilus shell.”
I wanted to visit the site, to reflect on an African narrative quite different to one taught to me at school in which nothing happened until the Portuguese showed up about 500 years ago.
In passing, it is worth reflecting on what Africa meant 2 000 years ago. Casson writes: “The term Africa here has a rather special meaning. Used politically, it was the name of the province that the Romans fashioned from the conquered Carthaginians territory.
“Used geographically, it often referred to the northern coast of Africa westward of Egypt, and sometimes, as today, to the whole continent, although that was ordinarily called Libya.”
I wanted to better understand the captain and his 66-paragraph periplus. My reading of the Periplus revealed a thoroughly modern person. Although his world was one of multiple gods, and the maps of explorers more than a millenia and a half later would chronicle a here-be-dragons world, his account is one of a rational man looking to do business.
Casson writes: “Curiously, one subject he gives short shrift to is religion. Although he came from Egypt, the land par excellence of religious memorabilia, and his chief trade contacts were with India, where, in his day as in ours, religion was of great moment, he mentions but a single religious monument, the shrine of Durga near Cape Comorin.”
I would, like him, sail to Mafia Island, in my case on a dhow, the vessel with iconic triangular sail that define this coast, but research told me dhow trips are now pretty much localised.
I instead flew in to Dar es Salaam with my bicycle equipped with tent and kit. If I could hitch a lift by dhow, fine. Failing this, I would ride, taking in the Swahili coast and its people.
We don’t have a name for our merchant but he would start his journey at Berenice on the Red Sea, it being one of two ports, the other Myos Hormos [Mussel Harbour], where goods were transferred across the desert to and from the Nile.
I made my way down the coast, noticing some secondary roads are not on Google Maps, my only navigating tool. At an overgrown, almost disused lodge with just a single chalet standing and monkeys having taken charge, I was told of a captain, Yambiyambi, at the next village, Buunyi, who could take me to Mafia. Buunyi was also not on the map.
As I rode the next day, I found myself repeating: I am riding to Buunyi, a place not on the map, to meet a man called Yambiyambi who will take me to Mafia Island.
Ten kilometres later I was at Buunyi. The dirt road ran through a line of makeshift shops. A plantation of soaring coconut trees stood between the shops and the shore, which hosted a set of high-and-dry fishing boats.
Two men were cooking breakfast at one well-aged boat propped up with poles on either side to stop it falling over. A few dry fronds provided a little cover. The men had no interest in me and didn’t want to be photographed.
I asked for Yambiyambi. No one knew him or had heard of him. This got to be a joke; some of the fishermen started calling me Yambiyambi.
A group of men were fixing boats using an mattock and a hand drill, where a bow (of a bow and arrow) makes a drilling action much like some hunter-gatherers made fire. I was later to read in Ships Fastenings: From Sewn Boat to Steamship by Michael McCarthy that this drilling technique was used in ancient Egypt and is described in book IX of Homer’s Odyssey.
The fishermen spoke as little English as I do Swahili. But one captain could take me; the trip would last 10 hours. The asking price did not seem unfair but was beyond the cash I had on me and I was not sure I’d be able to get more on Mafia Island.
I was also a little unnerved, not that I doubted their seamanship but because whenever they spoke of Mafia, they pointed east into the middle of the ocean. I was expecting them to indicate south.
I rode on.
After a while I joined the main, tarred road, instantly understanding why there is little to no dhow transport. I turned off the main road and headed towards Nyumatsi, also not on Google Maps, where the ferry leaves for Mafia.
I arrived at Nyumatsi at about 6pm, to learn the ferry would leave at 9pm or 10pm. I ate, booked a seat for myself and a space for my bike, and waited. The women, brightly adorned, sat together on a canvas with their luggage. The men waited elsewhere.
There was no sign of the ferry. After some time I looked at my watch. It was 1.30am. We left at 4am, all seating and sleeping space taken. There was half a space in front of me: a woman curled into it. We arrived at 8am.
The next day I rode on the main road, fortunately dirt, the navigation backbone across the island, to Jimbo and then backtracked to Jojo, the closest village to the underwater ruin.
The road ended at a school. A meeting of the school board, I guess, was taking place under a tree. I told them why I was there and asked whether I could pitch my tent. I would have to get permission from the village president; in the meantime I was invited for lunch.
Presently the president arrived. I would need authorisation from two other presidents; a regional and district one, as I understood it. The nearest lodge was 20km away. I was where I needed to be, so near, yet really far.
I retraced my route, passing fishermen’s homes on the ocean, with the submerged site just a few kilometres away, but there were no English speakers. I rode to the next village, Banga, stopping at a clinic. The medic in charge took me to the village square where a carpenter phoned its village president. He arrived soon after, on the carrier of a bicycle. A jovial man, he had a warm handshake.
A serious conversation followed about the mgeni (foreigner). I thought it would be another no, but I was invited to stay in the hospital — actually the staff quarters for the clinic. A room was made up for me.
I realised, riding back the next day, I did not see a single policeman or police station on the island. The villages control law and order. If someone is attacked in their area, and given the friendliness of Tanzanians I’d say this is extremely unlikely, the village is responsible. But once you have the permission of the president, you have the protection of the village.
On the way to Banga I had found an English speaker, a bodaboda operator. These are the ubiquitous motorbikes that transport people and carry goods. His brother could take me by mtumbwi, dugout canoe, to the site.
But alas, when I returned the next day he was in a taxi heading to the other side of the island. Against all kinds of noise on the line and in the taxi I could only make out three words: “Wait one hour.”
It poured, me watching the rain fall and wondering whether I would ever get to the submerged site. But phone calls were being made and a plan seemed to be coming together. We’d walk a few kilometres where we’d meet men in a mtumbwi who’d pilot me to the site. A fee was agreed, plus bottles of water and biscuits.
We passed through coconut trees to the shore where, sure enough, a mtumbwi with two men made their way towards us. I was loaded into the dugout. You have to sit pretty still to avoid lowering the one side or the other. Either way, though, water comes in. The pilot in the back does a lot of bailing.
We headed towards Ras Mlundo, a spit of beach that sticks out, tongue-like, with a notable estuary behind it. The tide was going out. We beached. I could see no ruin, no reef, nothing.
But then, in the near horizon was what looked like a line of dhows, their sails stretched in the wind. It was breakers, crashing on to the northern wall of the ruin. I could instantly see the extent of it, the line running for several kilometres.
The pilots had made themselves comfortable on the beach. I walked a couple of kilometres out, the tide falling all the time. But as I neared the breakers I could see I’d have to swim another kilometre or so to reach it; not a good idea. What to do?
After a while the pilots launched the dugout, now using a sail rather than paddles. They picked me up. I pointed at the breaking waves and we headed towards them, getting pretty close, perhaps 50m or so, when turbulent water suggested getting closer would not be a good idea. We headed back.
I had been to the site but it did not feel quite satisfactory. Perhaps I needed to actually touch it?
My plan was to leave the next day but the ferry was full. At the Whale Shark Lodge I met Hassan Bakari, who knows all things Mafia. He also knew Sutton and the Swahili name for the ruin: mwamba ukutu, wall rock, a favourite fishing spot for locals, the ruin acting as a reef.
Hassan arranged for a motorboat to take me and two visitors from Canada, Mads and Amanda, to the site. We shouldn’t expect too much, he said, because it was neap, not spring tide.
We arrived at about 4pm when the tide was lowest, a line of breakers cresting the reef. Mads lent me a goggle and snorkel and we us jumped in, making our way to the rocks. Getting on was not too much trouble but the breakers threatened to wash us off. The rocks were encrusted with razor-sharp barnacles: a slip would have have produced blood.
The Periplus captain speaks of Rhapta as a port, a trading place. About 100 years later Ptolemy described it as a metropolis. This period falls within the Pax Romana, the 200-year highpoint of the Roman Empire. It is documented that there was very little Roman trade with the east via the Indian Ocean before CE 20. But it flourished after this; a market of 56-million people, one-quarter of the globe, clamoured for the best of what Asia, Africa and Arabia could offer.
But, says Casson, even at the time of the Periplus Rhapta must have been of considerable size if it accommodated, as Zanzibar did in later centuries, vessels and their crews while they awaited the shift of the monsoon.
After Raptha, the merchant captain recorded: “For, beyond this area lies unexplored ocean that bend to the west and, extending on the south along the parts of Ethiopia and Libya and Africa that turn away, joins the western sea.”
Slave trading is mentioned only three times in the Periplus but this is not to say that slavery was insignificant at the time. British historian Caitlin Green has shown in a paper, Sub-Saharan and Trans-Saharan Contacts and Trade in the Roman Era, that its principal trade with sub-Saharan Africa between the first and seventh centuries was in slaves, who were trafficked across the Sahara desert.
Colonisation was well underway at the time of the Periplus. “The region is under the rule of the governor of Mapharitis since by some ancient right it is subject to the kingdom of Arabia as first constituted. The merchants of Muza hold it through a grant from the king and collect taxes from it,” the captain tells us.
Mapharitis was a province in the ancient kingdom of Sabaeans and Homerites, in today’s Yemen, the Sabaeans being described in Assyrian times as early as 2 800 years ago. The Sabaeans paid “many embassies and gifts” to the Roman emperor, the Periplus tells us.
Is Sutton’s discovery Rhapta? He arranged funding for two of Chami’s PhD students who have started research mainly on the submerged site and vicinity. “The purpose is to find other materials such as artefacts of the Roman period,” Chami told me. “Initial survey of the submerged site suggests that underwater archeology is required to explore below the sand.”
But whether or not this is Rhapta, what happened to this site now under the sea? There is not in a single account of it after the Periplus and Ptolemy. It was a metropolis; then it was nothing.
When accounts begin again, such as one by Ibn Battuta, a Moroccan traveller who reached this part of the African coast in 1330, the trading centre of this region has moved about 100km south to Kilwa, which was a centre for gold trading. Rhapta was not mentioned.
*Rhapta was misspelled as Raphta in earlier versions of this story. Apologies.