The 2016 Rio de Janeiro Summer Olympics are less than a month away. Fans from around the world will tune in to watch and see if their country takes home the gold. In 2012, 219.4 millionpeople watched the watched the London hosted Summer Olympics in the United States, making it the most watched televised event in the U.S. at the time.

One of the most recognizable elements of the Olympics is the opening ceremony. The opening ceremony showcases and celebrates the culture of the host city and its country. Rio de Janeiro is famous for their lively and colorful parades. Featuring these parades as the Olympic torch is being lit would make for an unforgettable opening ceremony.

Over the past 20 years, the world has seen some spectacular opening ceremonies. In each of the five cities that hosted the Olympics during this time, they used all of their resources to put on spectacular and historical performances.

In 1996, the Olympics were hosted in Atlanta, Georgia. This year marked the 100th anniversary of the Summer Olympics and the Atlanta was under a lot of pressure to honor this anniversary.

$15 million was spent on just the opening ceremony and every cent went toward making history.

During the Atlanta opening ceremony, citizens of the world were treated to a celebration of the south. Musicians performed jazz music while surrounded by dancers, and Grammy winning Motown singer Gladys Knight, a Georgia native, performed “Georgia On My Mind,” which is also the state’s official song.

This was also the same year that the late Muhammad Ali, who won a gold medal for boxing in 1960, lit the Olympic cauldron.

Here is a clip of the historical moment, accompanied by comments from athletes who witnessed the event, and other Olympians who looked up to the boxer

Sydney hosted the Summer Olympics in 2000, and although they did not celebrate an important anniversary like Atlanta, the Australians were able to put on a record breaking opening ceremony. Some of the records include first Olympic flame carried underwater, first flame carried in a wheel chair and first mechanically moving Olympic cauldron.

The Sydney opening ceremony celebrated Australia’s aboriginal population with traditional dances and ceremonies and also recognized modern Australia by featuring surfing. Australian actress Olivia Newton-John and 1980s Australian pop singer John Farnham also performed the song “Dare to Dream” as a part of the ceremony.

The video below contains a compilation of moments from the 2000 Summer Olympics opening ceremony, including the different records broken while carrying the torch.

The Olympic games went back to their roots in 2004, when the event was hosted in Athens. During the opening ceremony, Greece’s important contributions to society were focused on, including Greek philosophy and Greek mythology.

Despite their financial struggles, Athens was able to put on an impressive opening ceremony, which became the first opening ceremony to include a holograph and the first to fill the stadium floor with water.

This clip from the 2004 broadcast of the opening ceremony, features a series a floats that capture different moments in time during Greek history, including the first Olympic games.

One of the most impressive and elaborate opening ceremonies was performed during the 2008 Summer Olympics in Beijing. Beijing honored their creative history with impressive drumming sequences, difficult stunts and spectacular special effects.

The 2008 Olympics marked the first time a stadium was built specifically for hosting the opening ceremony and the first time the Olympic cauldron was lit by a suspended torchbearer.

Due to financial freedom and nearly limitless resources, Beijing was able to present an opening ceremony of grand scale and beauty. This opening ceremony inspired the world and changed the game for future opening ceremonies.

This clip from the opening ceremony showcases the scale of human effort put into the ceremony, and the evolution of Chinese characters.

The most recent Summer Olympic event was hosted by London in 2012. The London opening ceremony was directed by film British director Danny Boyle, and was a cinematic celebration of the United Kingdom’s history and culture. British characters like Mary Poppins, James Bond and Harry Potter were featured in the performance and British pop culture was a main element of the night.

Performances by British musicians, like Paul McCartney and the Arctic Monkeys were also included in the ceremony.

Although London did not perform a ceremony at the same scale as Beijing, their opening ceremony moved the technological aspect of the opening ceremony forward, by including live film production and LED screen effects.

In this introductory clip to the opening ceremony, Queen Elizabeth II and the current James Bond, Daniel Craig, make their way to the opening ceremony. This clip captures a bird’s eye view of London, and also contains a bit of quirky British humor.

Tokyo, Japan is set to host the next Olympic games in the summer of 2020. With Japan’s contributions to the world of technology, their opening ceremony is also highly anticipated.

As technology and creativity continue to grow, the opening ceremonies will break records and test the limit artistic capabilities.

Within the time span of these opening ceremonies, the world has changed dramatically. Through the opening ceremonies, each city has been able to tell the story of their country and unite the world as a captivated audience.