Booked into a hotel but not sure about the neighbourhood? Make sure you pack a belt.
A Royal Marine commando with a large self-defence social media following has revealed his must-pack travel accessory.
Robin who shares his defence tips via TikTok page DutchintheUSA has explain how you can sure up even the most low-rent hotel room.
Demonstrating the technique in a short video - he loops the belt through the bolt chain and round the handle of the door, making it impossible to enter. Even with a key.
"Use your belt to go through the chain link. This makes it harder to pick it or even remove the lock."
The Marine says he has often stayed in some sketchy place and the trick has never let him down. Other tips for combating hotel-room intruders include leaving a glass on the door handle, to make sure you don't sleep through a break in attempt.
One imagines the self-defence guru's tips are a bit overkill for your average BnB - but you can never be too secure.
In a step-up from the technique of using an upturned chair to block a hotel door - as done in the best spy thrillers - Robin advises using a curtain rail instead.
If your shower curtain detaches easily, the metal rod can be used as a door jam.
Referring to the technique as a "self-made barrier" - it can be used to jam the door shut, propping it between the door and the wall in a "triangle".
While some viewers advised Robin to check into hotels which spent more effort on security, he advised these techniques were not restricted by hotel star-rating.
However other viewers said they would bear these techniques in mind for the next time they booked into a sketchy hotel or were travelling alone.
Other commentators said they were ideal tips for solo female travellers, and would try it on their next trip.
"Everyone thinks 'it will never happen to me' until it does. Better to be safe than sorry," said one fan.