L'Arche London's 40th anniversary celebration To celebrate the 40th anniversary of L’Arche London there will be an inclusive service of thanksgiving at Westminster Cathedral on Saturday 14th July. The ceremony, which will bring to a close a year of celebrations that began last summer, will be led by Bishop Nicholas Hudson. There will be a performance by the Movement in Worship drummers and Stephan Posner, International Leader of L’Arche, will give the keynote address. The service begins at 2.30pm in Westminster Cathedral and everybody is welcome to attend. The nearest tube station is Westminster, which has step-free, accessible (lift) access.