A not-to-be-missed experience when visiting Hon Bay Canh Island of Con Dao Archipelago is to release baby turtles back to the ocean at dawn. 

Dawn breaks over Con Dao, a top tourist attraction in southern Vietnam, as seen from Con Son, the only inhabited and largest island of the 16-island Con Dao Archipelago.

Most visitors to Con Dao stay on Con Son before exploring smaller surrounding islands, of which Hon Bay Canh (Bay Canh Islet) is the best known.

Located in the southern province of Ba Ria - Vung Tau, around 230 km (143 miles) southeast of Ho Chi Minh City, Con Dao was once dubbed ‘Hell on Earth’. Before 1975, it formed the biggest prison in Indochina, run by French colonists and later by American troops in the Vietnam War.

From Con Son Town, it takes 20 minutes by speedboat to reach Hon Bay Canh where visitors could relish the opportunity of releasing baby turtles back to the ocean or watching mothers lay they eggs on the beach.

The tour usually starts at 6:30 a.m, so visitors should gather at the pier early.

Hon Bay Canh is the second largest island of Con Dao Archipelago after Con Son. Located to the east of the island chain, Hon Bay Canh is covered by primitive forests, boasting 882 plant species and 150 species of animals.

Visitors to the islet are first introduced to Hon Bay Canh ranger station and the conservation and life cycle of turtles.

In April to the end of October every year, over 400 green turtles and hawksbill sea turtles, scientific name Eretmochelys imbricate, come to Con Dao waters to lay their eggs on Hon Bay Canh, Hon Cau, Hon Tre Lon and Hon Tai islands.

Over 150,000 baby turtles have been rescued and released back to the ocean with a hatching rate hitting 87 percent. Con Dao National Park has been recognized by Vietnam Record Book as having released the biggest number of baby turtles back to the sea nationally.

Each group of visitors is given baskets containing baby turtles, released from Bai Cat Lon Island. Staff clearly instruct tourists not to obstruct the turtles' passage, step on, or physically touch the animals.

Releasing baby turtles back to the ocean must commence early in the morning to avoid harsh sunlight and high tides.

The turtle species has seen a steep decline elsewhere in Vietnam, with the number of animals laying eggs annually in the country decreasing from around 10,000 in the 1980s to 450 in 2019, a study by the Institute of Marine Environmental Research found.

The species is threatened due to pollution and loss of nesting areas because of coastal development, coupled with their inherently slow growth, maturity and reproductive rates.

Most sea turtles are classified as endangered and needing prioritized protection. Hunting or trading them, listed in Vietnam's Red Book of endangered species, is a crime in the country.

After releasing the turtles back to sea, visitors have the opportunity to learn about the ecosystem of Con Dao's mangrove forest, formed and developed on the surface of dead coral reef, sand and soft clay - a unique feature that is rare elsewhere in Vietnam.

Visitors to Hon Bay Canh can also enjoy swimming and snorkeling amid the coral reefs.

The tour to release turtles back to the ocean combined with coral diving usually lasts half a day and costs VND800,000 ($34) per person.