See some of the world's most dangerous beaches:

Zipolite Beach. Mexico.

Zipolite Beach. By h-ibrido

Playa Zipolite, a beautiful tiny beach of white sands and crystal waters, is tempting but lethal. Located in Oaxaca, the southern state of Mexico, Zipolite has taken numerous lives. The name itself is quite alarming as in the Zapotec language it means "the beach of dead" due to its strong undertow and changing rip currents. The turquoise waters of the playa lure unaware travelers whereas locals prefer to stay away.

Among most dangerous periods when swimming is almost impossible are the so-called rebalses - the periods when the water "rebels". It is a time of high seas that follows a full moon and lasts around 3 days. Rebalses are stronger and occur more often from April to June.

Since the establishment of a professional guard program at the end of 1990s there have been fewer fatal accidents at the beach, though extreme caution is still advised.

If you decide to swim in Zipolite's waters stay close to the shore and do not enter the water when you see red flags.

Zipolite Beach By Kevin Hutchinson

Hanakapiai Beach. Hawaii.

Hanakapiai Beach. By Dimmerswitch

The breathtaking Na Pali Coast on Kauai is home to the world's most beautiful but treacherous beaches. As there are no big reefs that could hamper the strong ocean currents, the coast is extremely unsafe.

Among the most risky beaches is Hanakapiai - the 2 mile (3.2 km) long stretch of golden sand along the popular Kalalau Trail. Similarly to Zipolite, it is the powerful ocean that takes control over the Hawaiian beach. Strong rip currents, rip tides and shore breaks make swimming very risky here.

According to the sign posted on the beach at least 82 people have drowned here (as of December 2008). The waves are so large and strong that they can sweep away people who are just wading in the water and are not deeper than up their knees. Moreover, due to the Kauai's geography, if someone gets caught in a current the nearest safe shore is around 6 miles (10 km) away.

Hanakapiai Beach. By colorlessnes

Hanakapiai Beach. By AZAdam

 Praia de Boa Viagem. Recife. Brazil.

Praia de Boa Viagem on Sunday. By Marcio Cabral de Moura

The urban beach of Recife, a beautiful coastal town often called the "Brazilian Venice", is home to an extremely popular beach, Boa Viagem. It is one of the most visited beaches on Brazil's eastern coast, but unfortunately, it's popular with sharks, too.

Before the 1990s the sharks did not use to attack humans in the waters of Boa Viagem. Nevertheless, between 1992 until 2007 there were around 50 reported attacks (19 of them fatal) along the relatively short, 12.5 mile (20 km) long coast.

What factors have contributed to the increase in the number of attacks? It boils down to the destruction of the marine ecosystem that used to provide food for these carnivorous predators. The untreated sewage, industrial effluents, and increasing numbers of fishing boats have damaged the local reefs and reduced the marine biodiversity.

Moreover, Port Suape that opened in 1984 has emerged in the southern estuaries where bull sharks (by the way, one of the species most frequently recognized in attacks on humans) used to give birth. Therefore, the female sharks had to move to the next estuary, the one close to the city's main beach.

Sharks Warning Signs in Recife. By teufel

New Smyrna Beach. Florida. The USA.

New Smyrna Beach. By var resa

Another shark-infested area is Florida, the USA. In fact, the majority of unprovoked shark attacks on humans in 2008 took place in North American waters. According to the ISAF (the International Shark Attack File), there were 118 shark-human incidents and 59 unprovoked attacks worldwide, of which 42 (71%) occurred in the USA and 32 in Florida. Among Florida's most dangerous beaches is New Smyrna Beach in Volusia County that reported 22 shark-human interactions in 2008.

Nevertheless, the ISAF underlines that the high ratio of incidents is caused by the fact that people have been spending more and more time in the water and the number of Florida's beach visitors has been gradually growing over the past decade. Moreover. the experts point out that the Floridian sharks are not dangerous for people as these are mainly blacktips, blacknoses and sharknoses, and most incidents are not fatal. They add that you are more likely to win a lottery or be hit by lighting than eaten by the shark at Smyrna Beach.

When it comes to lighting the experts are actually right as between 1997 and 2006 there were 71 fatal accidents related to lighting in Florida. The New Smyrna is often evacuated and closed for days because of that danger.

New Smyrna Beach. By Brenda Y

The Northern and Eastern Beaches. Australia.

Queensland. Australia. By pommypaul

Australia, famed for its excellent beaches, is home to one of the world's most dangerous creatures. The biggest beach threat comes not from sharks and ocean currents but the almost invisible Australian Box Jellyfish - the Chironex fleckeri. The jellies are among the most venomous creatures in the world and their venom is most deadly in the animal kingdom. There have been over 5,568 deaths recorded worldwide since 1954.

The box jellies can be mainly found in the northern waters of Australia, from Darwin, down the eastern coast, to Queensland. The season for the Chironex starts in October and lasts until April.

If you get stung by the box jellyfish, never use alcohol to pour over the sting. The best neutralizer for the stung area is vinegar that disables the box jelly's nematocysts.

Box Jellyfish Warning Sign in Queensland. By cthulhia

Box Jellyfish. By VannaGocaraRupa

Care for a swim?

Tags: beach, sharks, box jellyfish, dangerous beach, ocean currents, rip current, undertow, vinegar, rebalses, beach of dead, lighting, bull shark, ISAF