Updated

Paris officials pulled out all the stops Sunday in a bid to host the 2012 Olympics (search), transforming the Champs-Elysees (search), its most famous avenue, into a sports playground lined with wrestling mats, a running track and even a huge swimming pool.

Thirty-eight Olympic sports displays marked Paris' most over-the-top pitch yet to land the games, one day before the International Olympic Committee (search) issues its key report evaluating the five candidate cities. The others are New York; London; Moscow; and Madrid, Spain.

The sporting complex, which also featured tennis courts, equestrian rings, a beach volleyball court and kayaking basins, came with a hefty $2.7 million price tag.

Hundreds of frenzied workers erected the venues overnight. Later, French dignitaries and an A-list of national sports stars arrived at the Champs-Elysees to tout Paris' bid.

The contest for the 2012 Games enters a final stretch Monday, marking a 30-day countdown to the IOC's decision about which city will be the host.

"On July 6 in Singapore, the IOC members will have seen these images of mobilization and public merriment — an expression of our love of the games," French Sports Minister Jean-Francois Lamour told LCI Television.

"Paris expects the Games in 2012."

In Madrid, nearly 500,000 people began celebrating Sunday in a street party that included sports exhibitions, concerts and fireworks to showcase the city's 2012 Olympic bid.

Not everything went according to plan, however.

A flag measuring 11/2 miles long and 21 feet wide — described as the world's biggest — ripped in two when 1,500 volunteers unfurled it along the boulevard. It was soon tied together and the party continued.

The city's main thoroughfare — the Castellana Boulevard — was closed to traffic as athletes demonstrated their sporting prowess among children, alongside musical performances, clown shows and other festival events to show the city's "Olympic Passion."

The city also staged a round of the Triathlon World Cup in the morning and was hosting an exhibition handball match in the afternoon to raise funds for victims of the Asian tsunami.

Three of Madrid's landmark buildings also have been illuminated with the colors of the five Olympic rings for the celebrations.

"It will be the best way to show the whole world our passion for sport and our vocation for being awarded the Olympic Games," Madrid Mayor Alberto Ruiz-Gallardon said.