Normally, it would have marked the end of months of hard winter training and in the process raised millions of pounds for charities.

But because of coronavirus the event has been postponed until 4 October, leaving a big gap in the running calendar and charities' finances.

Were you due to run? Do you still have plans for the day? Have you discovered any interesting ways to keep fit during lockdown? We want you to tell us about it.

Organisers of the UK's major mass-participation events - including the London Marathon - have launched a campaign to help charities raise money and keep the public fit.

The 2.6 Challenge is intended to inspire people to create their own athletic activities based around the numbers 2.6 or 26 - and raise money through sponsorship and donations.

We want to know what ideas you have - and are looking to showcase the best of them in a live page on the BBC Sport website on Sunday morning.

Just fill in the form below - but please remember the activity must be within government guidelines on social distancing.

Saturday 25 April: BBC One will show a special programme on world record-holder and four-time London winner Eliud Kipchoge as the Kenyan explains how he became the first human to break the two-hour barrier. It begins at 13:15 BST.

Sunday 26 April: The day the 40th edition of the race was due to take place, BBC One will look back at 1981's inaugural London Marathon from 14:00 BST. There will also be live text on the BBC Sport website from 10:00 BST finding out how you are making up for the race's absence.