According to Official Guinness Records,
The largest parade of Mini cars consisted of 1,450 Minis and was organised by the London & Surrey Mini Owners Club as part of the London to Brighton Mini Run, Crystal Palace, UK, on 17 May 2009.
The 2-mile course was round Crystal Palace Park with the majority of the Minis part of the London & Surrey Mini Owners Club with other mini drivers coming from around the UK and as far as the Netherlands.
For a complete list of 2009 records, please visit 2009 Guinness Records in United Kingdom.