Olympic rings launched onto River Thames Olympic rings, mounted on a barge, are positioned in front of Tower Bridge on the River Thames in...

Olympic rings launched onto River Thames

Olympic rings, mounted on a barge, are positioned in front of Tower Bridge on the River Thames in London February 28, 2012.(Photo/Reuters)

Backdropped by the historic Tower Bridge, a giant Olympic Rings floats on the River Thames in London in the run-up for the Olympic games, during its launch to mark 150-days until the start of the London 2012 Olympic games, Tuesday, Feb. 28, 2012.(Photo/AP)

Giant Olympic Rings on a barge float next to the Thames Barrier on the river Thames in London. (Photo/AFP)

LONDON, Feb. 28 (Xinhua) -- London Mayor Boris Johnson launched giant Olympic rings measuring 11 meters high by 25 meters wide onto the River Thames on Tuesday, coinciding with 150 days to go to the start of this summer's Olympic Games.

The mayor also announced that the city will host a specially commissioned program of free cultural events to celebrate the London 2012 Olympic and Paralympic Games and create "a summer like no other".

From July 21 through to the September 9, in every borough across the capital, live music and performance, outdoor arts, spectacular and 'pop up' events will take place in high streets, town centers, parks and other surprise locations throughout the city.

Specially designed for all Londoners as well as the one million extra visitors expected each day during the Games, these projects and events will provide an extra layer of cultural activities as part of the "London 2012 Festival", underpinning London's international reputation for creativity and the quality and the breadth of its arts and culture.

"From museums to theater, and music to design, we have a reputation that is second to none and London's finest artists and organizations are producing an exceptional range of brand new cultural events that will add to the excitement of hosting the Games," said Boris Johnson.

The London Olympic Games will be held from July 27 to August 12.

Elsewhere, on the eve of the 150-day countdown, the British Olympic Association (BOA) announced plans for an Olympic Museum to be built on the future Queen Elizabeth Olympic Park (QEOP) as a permanent legacy of the London 2012 Games.

The proposals are for the Olympic Museum to open in 2014 and be situated adjacent to the ArcelorMittal Orbit tower. It is expected to become a leading visitor attraction on the QEOP.

The Museum will provide members of the public with a venue to re-live the excitement, passion and drama of the London 2012 Games.

It is also designed to recognize and celebrate London's unique place in the Olympic Movement as it becomes the first city in the world to host the Olympic Games three times.

BOA believes the museum will ensure the story of London's special Olympic history will be showcased to the world and assets from the 1908, 1948 and 2012 Games are shared with visitors for many years to come.