Perched away from the world on the rocky southern tip of Africa, the town of Hermanus rose to global whale-watching renown almost by chance.

Two decades ago, as South Africa emerged from apartheid-induced isolation, pop zoologist Mark Carwardine visited Hermanus while researching a book on the world's best spots to watch whales.

Carwardine knew whales swam in the frigid southern Atlantic waters, but when he inched open his curtains on one dreary rain-soaked day, he thought he had made a terrible mistake.

Then, from the warmth and comfort of his hotel bed, he spotted some Southern Right whales frolicking out to sea.

He pushed the bed to the window and continued to watch the show.

Carwardine was so impressed that Hermanus got its own book chapter -- titled "breach from the bed" -- and he described the town as having the "best land-based whale watching in the world."

It is a sobriquet Hermanus residents have embraced enthusiastically ever since.

The town was founded in the early 1800s by shepherd Hermanus Pieters, who followed an elephant trail through the steep mountain valleys to Walker Bay, but it was not until the 1990s that whale watching took off.

"There is much more curiosity now," said Ken Moore, who ditched his previous life in business to become a guide for Southern Right Charters as the boom began.

"There is good whale watching in (Mexico's) Baja California, Argentina and other places, but we have built great infrastructure here," said Moore.

South Africa, he said, also offers a touristic "surf and turf" for visitors, with the chance to see big cats and large marine mammals on one trip.

Cetacean tourism is now the lifeblood of Hermanus, which finds itself on the renamed "Whale Coast."

The town holds not one, but two whale festivals each year. It has its own legend of a girl named Bientanga from the Khoikhoi ethnic group -- whose language uses click sounds -- who communicated with the whales and brought them back to the town.

Wondering around the streets is perhaps the world's only "whale crier."

He uses a horn made of kelp to summon whale-hungry tourists to a jagged ocean cliff that serves as a viewing platform.

Just metres (yards) below are the Southern Right whales that drew Carwardine to Hermanus in the first place, and thousands of others subsequently.

"I'm pretty excited," said Desiree Neubauer, one Austrian tourist visiting with her boyfriend. "I didn't expect them to be so close to the coast."

Although found across the Southern hemisphere, Southern Rights are among the rarest of whales.

Around 12,000 of the species exist, compared to more than 100,000 Bryde's whales, which are also found along the Western Cape coast.

They were given their name by whalers, who thought they were the "right" whales to catch because of the species' large amount of valuable oil -- used for heating and in make-up -- and because they are docile and float after being harpooned.

Southern Rights grow to around 15 meters long (55 feet) and can weigh as much as 50 tonnes.

"That sounds like a lot, and it is a lot," said Moore. "To put it into context it's the weight of 10 African elephants."

They are baleens, meaning that instead of teeth they have hair plates at the entrance of their mouths which filter water for zooplankton.

Every June hundreds make the trip from the edge of the Antarctic to stay off the coast of Hermanus until around November, mating and giving birth.

They are also extremely playful, breaching, spouting and lobtailing at will, much to the delight of visiting tourists.