Chief Inspector Tony Callaghan from the Police Service of Northern Ireland (PSNI) is advising Londonderry festival-goers how to get to and from the Big Weekend event safely.
This weekend will see more than 35,000 people visit the Radio 1 site in Derry.
Chief Inspector Callaghan is confident there are enough stewards and police to monitor behaviour and make sure the festival is safe for everyone involved.
Calvin Harris, Biffy Clyro and Bruno Mars are headlining Big Weekend.
Other acts performing across the weekend include Olly Murs, The Vaccines and Foals.
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