The demonstrators in Belfast on Saturday want same-sex couples to be treated the same way in Northern Ireland as they are in the rest of the UK, where same-sex marriage is legal. The issue is a stumbling block to restoring Northern Ireland's Catholic-Protestant power-sharing administration, which has been suspended for more than two years.
Northern Ireland's 1.8 million people have been without a functioning administration since the government collapsed in January 2017 over a failed green-energy project. The rift later widened to broader cultural issues separating Northern Ireland's British unionists and Irish nationalists.
The socially conservative Democratic Unionist Party, an ally of British Prime Minister Theresa May's government, is opposed to a redefinition of the law.
Copyright 2019 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.