A busy town centre in south-east London has become car-free for the day to make way for a series of free events.
Greenwich closed to traffic on Sunday
Greenwich banned cars on Sunday as the Sea Britain 2005 festival, theatrical performances and Olympic-themed carnival dancers filled the streets.
College Approach has been transformed into a beach - with sand and deck chairs and "nautical events".
Elsewhere, several guided walks are being held from Trafalgar Square to celebrate National Walking Day.
Transport for London is involved and wants to persuade Londoners to walk more often.
In Greenwich, organisers also want to promote the message that people can have a great day out without using their car.
It is the fourth time the borough has held a car-free day, it is also setting up a "car club" to reduce congestion and air pollution.
Two roads leading into Greenwich town centre, King William Walk and College Approach, will be closed to traffic from 0700 BST to 1900 BST.
Greenwich deputy council leader Peter Brooks said: "It is important to find alternatives to car travel whenever we can, whether it be walking to school or cycling to work.
"The more we can do without our car, the better it is for our air quality, the environment and, as a result, our health."