A tidal warning, as the RNLI starts its summer patrols in Cornwall.

Lifeguards will be out on 36 beaches across the Duchy and Devon, from today.

Area manager Steve Instance says stuff like swimming between the flags and knowing your tide times can save lives: "When you're on holiday, all you want to do is have fun and often those thoughts of safety and what could go wrong are the furthest thing from your mind at the time. We're not there to spoil people's fun. We're trying to remind people to follow that safety advice, to have a look and to check the tides before they head to the beach.

"It's quite easy, when you're on the beach, to forget about the fact that the tide comes in and out but people really need to know what's happening; whether the tide's going out, coming in and whether that area that they're walking round the corner to, whether that's going to mean that they're going to be cut off by an incoming tide".

RNLI Beach Safety Advice:

• Wherever possible, always swim at a lifeguarded beach. Go to www.goodbeachguide.co.uk to search for listings throughout the UK.

• Always read and obey the safety signs, usually found at the entrance to the beach. These will help you avoid potential hazards on the beach and identify the safest areas for swimming.

• When on a lifeguarded beach, find the red and yellow flags and always swim or bodyboard between them; this area is patrolled by lifeguards.

• Never swim alone.

• If you get into trouble, stick your hand in the air and shout for help.

• If you see someone in difficulty, never attempt a rescue. Tell a lifeguard, or, if you can't see a lifeguard, call 999 or 112 and ask for the Coastguard.