The shared access area will stretch for 800m and will not have any kerbs
Campaigners are protesting against plans to remove kerbs and convert a west London street to allow pedestrians and cars to share access.
Kensington and Chelsea council is spending £25m to improve traffic flow by transforming Exhibition Road into the largest shared space in the UK.
The West London Residents' Association (WLRA) said the changes will put elderly and disabled people at risk.
The council said the changes will be a "huge boost to residents and visitors".
Traffic is expected to slow to 20mph in the shared space area, which will stretch for 800m and will not have any kerbs or pedestrian crossings.
Kensington and Chelsea councillor Nicholas Paget-Brown said: "With over 100 personal injury accidents in the last three years alone, there is an urgent need to regenerate the Exhibition Road area.
"The shared space design brings substantial benefits for other groups such as wheelchair users, those with limited mobility and parents with pushchairs."
He added the council was working with Transport for London (TfL) to help visually impaired people understand the road changes.
The council is expanding shared space in the borough after it repaved the area outside Sloane Square Tube station in February to allow pedestrians and cars to use the same area.
The WLRA argue Exhibition Road will become a no-go area for visually-impaired people and will also endanger children.
Gordon Taylor, from the WLRA, said shared space developments are "an accident waiting to happen".
He said: "After several near-misses, the council is slow to admit that the Holbein Place shared space development is wrong and have been hesitant to re-install a kerb and light controlled crossing which would help make the crossing safer."
About 30 people from the Campaign for the Guide Dogs for the Blind, the National Federation of the Blind, the Taxpayers' Alliance and the WLRA joined the protest.
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