Largecrowds are expected in central London today to support the cause of same-sexmarriage.
Organisersfrom the gay and lesbian community hope it will be the biggest same-sex rally everheld in the UK.
9,000 people are expected to turn out.
150 gay and lesbian support groups from all over the UK will be parading through central London.
The parade route runs from Baker Street, along Oxford Street and Regent Street and ending at Trafalgar Square.