As Autumn takes begins Portugal remains a holiday hotspot, offering year-round mild and pleasant temperatures. But before you take a stroll on the beach or a dip in the ocean, travel expert Jessica Bollinger is warning that tourists must be aware of a simple mistake that could end in a fine of up to €750 – £625.

“Peeing in the ocean in Portugal is not just one of those unspoken rules” the expert from youth travel agency KILROY explains. “Whilst, granted, it must be a difficult law to police, it’s been put in place for a very good reason.”

Jessica explains, “the rule has been introduced for hygiene reasons, because urine is toxic to aquatic wildlife and can be destructive to the ocean’s biodiversity and coral reefs.”

So, whilst it may seem more convenient to pee in the sea, Jessica warns tourists to be wary of the hefty fine that could bring your European break to a sour end.

But holidaymakers shouldn’t panic too much. “Most public beaches will have toilets which can be used for free or for a small charge,” reassures Jessica. “The fine for using the ocean instead can be up to €750 so it’s definitely worth your time and wallet to take a walk to the public toilets!”

The UK’s Foreign, Commonwealth and Development Office also has warnings about holidays in Portugal. They say: “Crime rates are low but pickpocketing, bag-snatching and theft from holiday properties are common in major tourist areas. Foreign-registered and hire cars are often targeted by thieves. Thieves may use threats or violence.”

The Foreign Office adds: “Pickpocketing is a risk. Take care on public transport and at busy stations and crowded bus and tram stops. Check your holiday accommodation is secure. Lock all doors and windows at night and when you go out.

“If you’re worried about security at your accommodation, speak to your tour operator or the owner. Attacks or assault, including sexual assaults, are rare but do occur. The risk is highest late at night around popular nightlife locations.”

While travelling in Portugal, you must show some form of identification if asked by the police or judicial authorities. Sometimes a copy of the photo page of your passport could be enough, but you may be asked to produce the original document.