Rio de Janeiro's annual Carnival kicked off on Feb. 13 and will run through Feb. 17.

The festival officially started when the city's mayor, Eduardo Paes, gave the keys to Rio to the mythical King Momo, according to Yahoo via AFP.

"For the second straight year I receive the key to the city and declare Rio carnival open," said Wilson Dias de Costa Neta, 28.

The festival began in 1723, but it has changed along the years. For example, 1928 was the first time a samba school was formed, according to the Australian Broadcasting Corporation.

It started off as a religious celebration, but it has become an attraction to tourists. Every year, the colorful festival impresses.

Here are 10 of the most compelling images from the 2015 festival.

1. Two women were bejeweled green outfits. They belong to the Academicos de Santa Cruz samba school.

2. A group works on their float. They were preparing the float for the Feb. 14 parade outside the Sapucai Sambodrome.

3. A member of the Candomble religion poses on the second day of the festival. She wears all white, just as the rest of her group does.

4. On Feb. 14, a float sat waiting for the parade. The intricate details of the float, namely the large sunflowers and the green shells, and the time spent putting together the float can be seen.

5. A group of performers pray before the festival. The group has painted themselves in gold, and one wears a sign that says "buy if gold."

6. A woman throws confetti while another person takes a selfie. The group was at the at Sky on Earth parade on Feb. 14.

7. Candomble religion members open the second day of the festival, as they pose in front of their float on Feb. 14.

8. Even before the carnival kicked off, there were interesting scenes. G.R.E.S. Sao Clemente samba school members rehearsed before the festival and put on what seems like a fun routine.

9. A dancer from the G.R.E.S. Sao Clemente samba school rehearses one last time. The woman is caught mid-twirl.

10. Brazilian singer Daniela Mercury wears a colorful, bold outfit on Feb. 13.