This is the time of year travellers from around the world flock to the streets of Rio de Janeiro and Sao Paolo in Brazil, to mingle with samba-dancing crowds, bikini-clad Brazilian beauties and people in outlandish costumes.

This is the time of the Rio Carnival - the street party against which all other carnivals in the world are measured.

Rio's famed Carnival was kicked off by the portly King Momo - the event's mascot (of a sort) under a stream of confetti and with lively music. The event, which started on Saturday 9 February, also boasted the first of many traditional parades through the city's Sambadrome.

Rio Carnival 2013 was declared officially open when Rio's Mayor, Eduardo Paes, handed the city's keys to King Momo, saying: "The time has come to hand over my duties to magnificent King Momo so that city may have fun under his rule. Let there be peace and joy."

King Momo then declared the event open. Despite weighing 150kg, he then broke into a graceful samba to woo the crowd.

This year, there is a sombre tinge to the event, which remembered the people who recently died in a nightclub fire. President Dilma Rousseff will not be taking part in the five-day event and will instead attend a memorial for the fire victims.

The Rio Carnival 2013 continues till Fat Tuesday (12 February) and more than a million people are expected to take to the streets, soaking in the colours and sounds of Brazil. The Carnival is staged across the country, in such cities as Salvadore, Recife, Olinda, Manaus and Porto Alegre.

Korean Memories

There will be a serious aspect to the Rio Carnival 2013, aside from remembrances for the victims of the nightclub fire. Rio Carnival 2013 will pay tribute to Korean immigrant workers.

And just for that, Korean pop sensation Psy is in Brazil and he will perform during the Carnival, with top Brazilian singers Claudia Leitte and Gilberto Gil.

Meanwhile, other international stars, such as actor Will Smith, rapper Kanye West and actress Megan Fox, will attend the Rio Carnival 2013.

The Carnival's blue ribbon event will be the Samba parade and the Samba competition, which will be fiercely fought between the two hundred Samba schools in the city of Rio. Held in the Sambadrome, they will be judged on their costumes, dances and floats.

The Carnival is thought to generate over £400m for the economy and will also be a test of the country's infrastructure and organisational skills. The South American giants are set to host the 2014 FIFA Football World Cup and the Summer Olympics 2016.

Click Start to see a slideshow of vibrant, colourful and stunning images from Rio Carnival 2013

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The Rio Carnival 2013 was kicked off by the portly King Momo - the carnival's mascot - under a stream of confetti and with lively music. King Momo was handed the key to the city by Rio de Janeiro Mayor Eduardo Paes. The mayor said: “The time has come to hand over my duties to magnificent King Momo so that city may have fun under his rule. Let there be peace and joy.”

A reveller from the Jacarezinho samba school takes part in the first night of the A Group annual Carnival parade in Rio de Janeiro's Sambadrome. Some of the Samba schools will spend up to £3m on their outfits, preparations and their elaborate floats.

Revellers from the Jacarezinho samba school take part in the first night of the A Group annual Carnival parade in Rio de Janeiro's Sambadrome. Rio’s poorest make up half the strength of Samba schools.

Revelers from the Jacarezinho samba school pose as they prepare to taking part in the first night of the A Group annual Carnival parade in Rio de Janeiro's Sambadrome. Smaller local street parties called ‘blocos’ are held across the city before the annual Rio Carnival to get the revellers into party mode before the actual thing starts.

A dog takes part in the "Blocao" dog carnival parade during pre-carnival festivities along Copacabana beach in Rio de Janeiro. February is the hottest month in Rio but that does not stop people from partying throughout the day.

Dogs wear the jersey of the Brazilian national football team, during the "Blocao" dog carnival parade during pre-carnival festivities along Copacabana beach in Rio de Janeiro. The consumption of beer jumps 80 percent during Carnival time and tourist influx is 70 percent of the normal.

A reveller from Paraiso do Tuiuti samba school dances dances atop a float during the second night of the A Group annual Carnival parade in Rio de Janeiro's Sambadrome. The Rio Carnival originally mimicked the European style of celebrating the advent of Spring. Later, they absorbed elements from native North American and African cultures.

Revellers from Paraiso do Tuiuti samba school dance during the second night of the A Group annual Carnival parade in Rio de Janeiro's Sambadrome. The underground Tube system in Rio de Janiero works 24x7 during the Carnival.

A reveller from the Jacarezinho samba school takes part in the first night of the A Group annual Carnival parade in Rio de Janeiro's Sambadrome. Street food is the best option for budget travellers. Hotels in Rio at this time of the year charge almost £10 for a plate of French fries.

The Sambadrome is the official venue of Rio Carnival and will host events of the 2016 Summer Olympic Games. The Sambadrome is divided into various sectors, or sections, and offers a variety of seating options, ranging from luxury suites to open-air bleachers. The sectors are located along the 700 meter (roughly half-mile) stretch of the samba runway.