Here are some easy and useful tips from The Traveling Professor. Travel safely!
Avoid Crowds and Crowded Areas: This is what concerns me the most. Avoid long lines and places where people congregate in a stationary or semi-stationary manner. For example, avoid long, slow moving lines by having cards like the Paris Museum Pass or the Rome Roma Pass. These items give VIP, no-wait-in line access to attractions without having to wait in line.
Take the Bus, Not the Metro: To me, it seems like it would be easier to get off a bus in an emergency situation rather than trying to get out of a metro station, or even worse, between metro stations.
Plan an Escape BEFORE an Emergency: I always investigate hotel emergency exits upon check-in. I try to pick restaurants with an alternate way out, just not a single entrance/exit way.
Check in at the Airport Early and Travel Light: I always feel like a "sitting duck" at the check-in area of the airport in the unfortunate even of a terrorist attack. My advice would be to get into the secure area quickly. This can be done by checking in the night before and by only using carry-on luggage. Priority access such as TSA pre-check helps too.
Be Aware: See an unattended bag? Get away and say something to a police officer or safety official. See a demonstration or protest? Walk away.
Carry Trip Interruption Insurance: With the right insurance, you can get out of a country more quickly in case of certain emergency situations.
Choose Destinations Wisely: There are places in Europe and South America with less chances of a terrorist act occurring. Consider that when choosing a place to travel.
Always Carry at least a Passport COPY: Write on it your name, medical conditions, hotel you are staying at, contact info at home. Carry a city map too.
Leave an Itinerary with Someone at Home: Make sure family or friends can get in touch with you while traveling.
And if There is an Emergency Situation: Try your best NOT to panic and for God's sake, help your fellow man.
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