Solidarity Week Mass highlights Global Solidarity Partnership with Dioceses of Wilmington and San Marcos. Since 2003, the Diocese of Wilmington and the Diocese of San Marcos, Guatemala, have been involved in a Global Solidarity Partnership. Each April, the partners hold a Solidarity Week to coincide with the Feast of Saint Mark on April 25. This year, the week began with a Solidarity Week Mass on Sunday, April 18 at Saint Catherine of Siena Church in Wilmington.