• pascalo, the distance is seriously the least of your worries. You'll easily be fit enough--it's not a race. Make sure that you get the rest of the logistics right. From memory, there are some posts upthread that explain what you need to do, and do refer to the Southwark Cyclists FAQ:

    http://southwarkcyclists.org.uk/social/dunwichfaqs09.shtml

    Just make sure you enjoy yourself!

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