Peta’s long, wonderfully descriptive letters to her mother tell of chance meetings with strangers and how their agenda changed daily, depending on who they met, the vagaries of public transport and even the vicissitude of the weather. They leave you with that feeling ‘If only…’ I’m reminded of the poem ‘Maud Muller’ by John Greenleaf Whittier:

For of all sad words of tongue or pen, the saddest are these: ‘It might have been’.

On 6 June 1978, Peta wrote to her mother giving her an update of their travels: ‘We didn’t go straight to the Yucatán from Oaxaca. Instead, we caught the bus to Villahermosa and met an English couple on their way to Bolivia through Belize so we decided to go with them as Belize boasts the longest reef in the western hemisphere. As we were full up of ruins, having spent the last few days at Mitla, Yagul and Monte Alban in Oaxaca, we thought some snorkelling was in order.’

On the way to Belize they stopped in Chetumal. A city on the east coast of the Yucatán Peninsula, Chetumal is an important port for the region and operates as Mexico’s main trading gateway with the neighbouring country of Belize and the rest of Central America. More than just a border town, in the 1970s there was strong evidence of an historical past inherited from Mayan ancestors, and the impressive bay was a riot of enticing turquoise and jade hues.

Peta continued: ‘We stopped a night at Chetumal and drank the night away with a couple of Scottish soldiers. They said they would rather be in Northern Ireland on less pay and more danger than here! I didn’t understand their attitude especially as things with the Guatemalans have quietened down so that they’re unlikely to die here.’ [Belize at that time was a British colony. It wasn’t until some three years later in September 1981 that it gained full independence and became a nation state within the British Commonwealth. Guatemala to this day maintains a territorial claim over Belize.]

From Chetumal, Chris and Peta caught a bus south to Belize City, a journey of some seventy miles. Belize is a land of mountains, swamps and tropical jungle, bounded by Mexico to the north, Guatemala to the west and south, and the Caribbean Sea to the east. The Belizean coastline held a fascination for them because, as Peta says in her letter, it boasts a stunning coral reef and having experienced Australia’s Great Barrier Reef, they wanted to draw comparisons. It is regarded as one of the world’s last unspoilt destinations and of course in 1978, it was even more remote than it is today. The 386 kilometres of coastline (made a UNESCO World Heritage Site in 1996) is littered with lush jungle, beautiful coral reefs, cayes (a small sandy elevation on the surface of a coral reef) and deserted islands in the Caribbean Sea. Pocket-sized, Belize is the only Central American country where English is the official language.

Describing Belize City, Peta says in her letter: ‘I was amazed – it’s a town of about 40,000 people who all live in shacks. Actually, the houses are very similar to those in Queensland but just look shabbier. The people all speak English, of course, as well as Creole and Spanish, and they’re really friendly. The atmosphere is very relaxed and pretty poor. They have T-shirts here with the slogan “You Better Belize It”, which kinda sums the place up.’

The day after they arrived in Belize City, Peta describes in her letter how they went down to the harbour and took a ‘28-foot sloop owned by an English guy to Caye Caulker. He and his girlfriend (an Aussie from Darwin) have been sailing around the cayes for a couple of months having a very good time.’ Peta wrote the letter to her mother from the Marin Hotel, located on a small island off the coast of Belize called Caye Caulker: ‘There are several of these islands called cayes (pronounced keys) and this one [referring to the Marin Hotel] is the cheapest, the hotel room costs about £2 a night and there’s a shower too!’

In 1978, Caye Caulker was, as it still largely is today, entirely white coral sand and to the north there’s dense mangrove forest and diverse birdlife. The beaches and the crystal-clear, turquoise-hued waters of the Caribbean were picture-perfect, deserted and inviting.

Even to this day, Caye Caulker is described as possessing a rare rustic, laid-back charm in contrast to the hustle and bustle of the Caribbean’s tourist hot spots. Its bohemian, relaxed lifestyle attracts backpackers and offers convenient anchorage and storm refuge for local fishermen working Belize’s barrier reef and the coast.

Complaining about the warm, humid conditions of the tropical monsoon climate, Peta wrote: ‘It is 83 per cent humidity on average throughout the year! I feel hot and sweaty all the time. Luckily there is a constant gale force wind so it’s not so bad but it’s terrible at night, when the wind occasionally dies, the mossies and sand flies are out in force – I’m bitten all over. Unlike on Beachcomber Island in Fiji, the reef is some way from the island so we’ve been out on the Norma (the boat we’ve arrived on). The coral and fish were so disappointing after the South Pacific but I enjoyed snorkelling again though I was more aware of the possibility of sharks being in deeper water.’

Caye Caulker is used as a popular launch pad for scuba diving at the Great Blue Hole. With the owner of the Norma and his Australian girlfriend, whose exotic beauty was defined by her wild Afro hair, Chris and Peta made the two-hour sail to the almost perfectly circular Blue Hole, located in the centre of the Belizean Lighthouse Reef and literally a large sinkhole of water, 145m deep and 305m wide. Its depth gives it a deep turquoise blue colour and makes it one of the world’s most outstanding dive and snorkelling sites.

Peta describes their visit to this geographical phenomenon: ‘Today we went to the Blue Hole, just by the mangroves which line part of the caye. It has a channel, which goes right under the caye, though no one knows where it comes out. Very enjoyable!’

Giving her mother some local colour, Peta writes: ‘The conch shells here are unbelievable, I wish I had room to bring one with me. Also, the tortoiseshell is pretty and they have black coral here though it’s very expensive. They grow sugar here. Passing a refinery is lovely – just like smelling jam roly poly. They have a really neat pie shop on Caye Caulker – coconut cream pie, orange pie, banana cake, all irresistible – consequently my middle is getting fatter all the time. There are lots of tourists here – mainly Americans, so we are not short of company.’

It was later that evening after returning from their trip to the Blue Hole that they met one such American in the bar of the Marin Hotel. The owner of the Norma and his girlfriend introduced Chris and Peta to an American acquaintance of theirs called Silas Duane Boston. They had spent the last couple of months sailing to different islands and often snorkelled with him and a mutual friend called Brian.

A larger-than-life character, Boston (a dislike of the name Silas meant that he called himself Duane) had become well known in Belize City and amongst the caye’s handful of locals and the travellers who, like him, were drawn to Caye Caulker’s bohemian lifestyle and stunning Caribbean backdrop. Making friends and acquaintances was quick and easy in the relaxed holiday setting. With days of wall-to-wall sunshine, the stunning beaches and few cares in the world, greater than where to buy a bottle of cheap rum, life was pretty idyllic. Some six months before Chris and Peta had made the journey, thirty-seven-year-old Boston had travelled down through Mexico. He had set off from his hometown of Sacramento in California with his two young sons, thirteen-year-old Vince and twelve-year-old Russell, in a pickup truck. After their truck broke down in the port of Veracruz in the Gulf of Mexico, they hired another one and headed to Chetumal, the border town to Belize that Chris and Peta had stayed in. Knowing he would be searched at the border, Boston sold his guns, which he had brought with him.

With his weather-beaten, rugged looks, experienced seafaring skills and talent for storytelling, he was an engaging character with a devil-may-care attitude. His most prominent feature was his small, piercing blue eyes and, on his left forearm, he sported a large tattoo of a mermaid in green ink. What he lacked in conventional good looks, he made up for in megawatt charm, which he used with great success, particularly with women. A lady’s man and a raconteur, he had already been married five times.

Entering Belize, Boston decided to set up temporary home with his sons so he bought a small sailing boat, but soon after it sank in a hurricane. His father Russell, with whom he was close, travelled from Sacramento to Belize in April 1978 to see him and his two grandsons and he gave him some money to buy another boat, but this time bigger. Originally called the Marcia P, Boston renamed it Justin B, after his two-year-old son Justin by his fifth wife, Kathe, from whom he was divorced in 1976.

About 32ft in length, the Justin B was a basic, Belizean wooden sailing boat with no bathroom or home comforts. There was a cuddy (a small cupboard-like cabin) at the front and a cramped galley kitchen to the rear, which you could look down into from small porthole windows on the deck. Very much a working fishing boat it had a large box for depositing fish.

Without a licence to trade, Boston used the six-ton fishing smack to sail tourists to one of the many Belizean cayes or ferry them back to Belize City. It wasn’t long before he realised that the Robinson Crusoe way of life, making meals from the daily catch, was actually the favourite part of the trip for many vacationers. The cayes, with their lush jungle, palm-fringed, white sandy beaches, offered the opportunity to snorkel, swim and scuba dive, so Boston started to offer longer excursions. Mooring at a reef, he and his sons would hand out masks and fins to allow passengers to snorkel and they could spear the plentiful fish and lobsters for cooking.

Sometimes Boston would employ a girl Friday to help out with the cooking and he provided a big stewing pot down in the galley for making communal dishes for al fresco dining. He and his passengers would build a beach fire, gather coconuts and supplement the meal with a mixture of rice, beans, vegetables and spices, which he, or his girl Friday, would prepare in advance whilst everyone was enjoying the water sports.

For three months, Boston had operated a successful, lucrative business, but shortly before he met Chris and Peta, government officials had boarded the Justin B and told him that because he was American, he wasn’t allowed to work in Belize without a work permit. They told him he could immigrate, but without applying to become a legal resident, he was taking business away from the local Belizeans and destroying their livelihoods. Not wishing to draw attention to himself any more than he already had, Boston decided it was time to leave the area.

Eager to keep her mother up to date with their movements, Peta added a postscript dated 13 June 1978, to the letter to her mother (as was her habit if she couldn’t post it straight away):

‘Sorry I forgot to post this in Belize on Saturday so I am adding a little now as all our plans have changed… We originally meant to get the bus to Merida in the Yucatán but then an American named Duane Boston, who owns a Belizean boat called the Justin B, offered to take us up to Chetumal by sail so we decided to do that.’

Their clothes stuffed into two duffle bags, Chris and Peta had boarded the Justin B. Chris also carried his black medical bag, for his next medical job in Trinidad, and his much-treasured ‘boombox’, upon which he played his pre-recorded cassette tapes of seventies music. Between them, they carried at least $800 dollars in Thomas Cook traveller cheques.

Accompanying them on the voyage were a Belizean called Tom and a tall blonde woman called Sharon, who was in her mid-twenties and a flight attendant from Missouri who had struck up a sexual relationship with Boston.

The short voyage from Caye Caulker to the city and port of Chetumal was perhaps Chris and Peta’s way of testing the waters to see if they all got on. From there they visited Isla Mujeres, an idyllic Caribbean island about eight miles off the Yucatán Peninsula.

Returning south, they entered Corozal, where Peta wrote: ‘The pier is surrounded by millions of catfish and the water boils when anything gets thrown in. It is a slightly more civilised place with a bar with easy chairs as opposed to the usual benches and sand floor of Caye Caulker. It even boasts an ice-cream parlour – one flavour only – strawberry!

‘The guy who did most of the sailing for Duane, a Belizean called Tom, decided to stay at Corozal, so Duane wants to take the boat down to Costa Rica to sell it. Anyway, we thought it was an opportunity not to be missed.’

Interestingly, Peta links the reason for Boston wanting to sell the boat as Tom being no longer there to do the sailing – Boston had obviously not told Chris and Peta that he had been forbidden from trading in Belize. Did Tom decide to jump ship at short notice in the small sleepy town of Corozal because he had seen something in Boston’s character that hadn’t at that time been revealed to Chris and Peta?

They had sailed for about three days and it was long enough to convince Chris and Peta that they wanted to stay on board and do some more sailing. Agreeing they would pay $500 for their passage, Boston offered them the chance to sail, swim, snorkel and sample the more remote cayes in the south of Belize, after which they would disembark in Roatan, Honduras, some 220km down the coast and Boston would go on to Costa Rica to sell the boat.

From Corozal, they sailed along the coastline to Belize’s North Eastern fishing port of Sarteneja and then on to Blackadore Caye, west of Ambergris Caye. Blackadore was Boston’s favourite stop-off for swimming and barbecuing the day’s catch and he had often taken parties of tourists there. The Justin B conveniently had a short keel, which meant that Boston could easily anchor close and alongside the bleached white sandy beach on the leeward side of the caye.

Such is the outstanding beauty of this 104-acre island that it was acquired in 2006 by the Hollywood actor Leonardo DiCaprio to convert into a luxury resort and protected wildlife reserve. ‘It is like heaven on earth,’ DiCaprio told The New York Times. It is set to become one of the world’s most exclusive island retreats. Back in 1978, it was even more desert island existence and as near to paradise as you can possibly get so long as you were a backpacker.

Not wishing to join them in going further south, Sharon disembarked when the Justin B then returned to Caye Caulker, leaving Chris and Peta the only two tourists on the boat.

To two intelligent people it must have occurred to them that being on a boat with a total stranger could pose a potential danger. In fact, a boat out at sea is probably the most vulnerable place on earth. But any niggling doubts about Boston must have been pushed aside by the fact that his sons were accompanying them on the voyage. It would be natural to assume you were in safe hands with the father of two young boys.

Certainly, during their first few days on the boat all seemed well with the world. From Peta’s letter, one gets a sense that she and Chris enjoyed the relaxed lifestyle: ‘It’s very peaceful and we can catch fish for supper. There’s plenty of snapper and grunt, not to mention catfish, which is tasty. It’s incredibly hot here; everyone is sitting inside suffering. There are papaya and mango to eat, but no fresh vegetables (apart from potatoes and onions), which I really miss. Still, it’s a real kick being able to catch your supper. Tom, before he left the boat, made “fry-jack”, a flatbread fried with baking powder to make it rise – very good indeed – he was a baker and it was a pleasure to watch him work the dough.

‘This boat is not very comfortable. Originally a working boat, most of the below deck is taken up with a fish box so that it’s a bit cramped for cooking and sleeping. But during the day it’s super, just lying on the hatches and soaking up the sun while the boat flies along. Of course, we have been becalmed and then everyone just jumps into the water to keep cool. In spite of it being the rainy season we have only had rain a couple of times. But at night the sky is amazing – there’s lightning flashing on the horizon all the time, and with no thunder it loses its frightening effect and just looks beautiful. We have had thunderstorms as well, which are quite something on a boat.’