Madeleine vanished from Praia da Luz, Portugal, in May 2007. The couple have said they cling to hope that she could still be alive. Six months ago, a Polish woman named Julia Wandelt was given a jail sentence for harassing the McCanns.
At the vigil, neither Kate nor Gerry addressed the crowd. Sean is a swimmer hoping to represent Great Britain in the 2028 Olympics, while Amelie is a university student. Kate's uncle Brian Kennedy read a poem by Simon Armitage.
19 years. The search goes on to find our Madeleine, to achieve some justice, to make the world that bit safer.
In a social media post, the McCanns wrote: "19 years. " They added: "We remain very grateful for all our support... " The current status of the police investigation remains unclear, and no suspect has been charged.
We remain very grateful for all our support - from friends and family, people we know and those we don't - and from the police and authorities for their continued determination and effort. Thank you. For Madeleine, who we love and miss every day, we will never give up. Kate, Gerry and family.