Keep some potential threats in mind when your travel destinations may carry specific warnings about crime, bad weather and more.

Some people love to visit popular tourist spots and return again and again. Other, perhaps more fearless adventurers prefer charging off to far corners of the world where few have ventured.

Both are wonderful ways to travel but in either case, destinations may carry specific warnings about crime, bad weather and more — threats that can make or break a trip.

Here are five to keep in mind.

1. The threat of weird climate events

These are unusual events, to be sure, but they do happen. Examples include erupting volcanoes spewing ash that damage planes and sometimes shut down airports. Examples include the volcanoes that darkened skies over Bali in 2017, Iceland in 2010 and Indonesia in 1982.

Major earthquakes can close airports, too; it has happened in Mexico City (2017) and Tokyo (2011). Remember last year’s California brushfires? They temporarily closed airports and even some major arteries, including the 405 interstate that many drivers take to Los Angeles International Airport.

What can travelers do? Start by making sure airlines you fly have your correct contact information so they can get in touch if they need to pass on urgent messages. Then, pay attention to news reports that might affect your departure or arrival city.

Finally, as your trip approaches, follow your airline on social media; it’s the easiest way to see flight updates and get questions answered.

2. The threat of weather and maintenance delays and cancellations

We’ve experienced some particularly brutal winter weather this month, along with the ensuing domino effect of canceled flights and untold delays. But remember, delays can also be caused by something as simple as a broken plane door latch.

And while there’s not much you can do about Mother Nature or maintenance issues, you can stay in contact with your airline. If you are already at the airport when you hear of delays or cancellations, get in line to talk to an agent but also get on the phone (you never know which will be faster).

The good news is airlines have become pro-active at identifying delay issues like storms and most are offering to waive change fees well in advance. Take advantage of this so you can rebook a flight you actually want instead of getting moved to a flight that’s convenient for the airline.

3. The threat of crime or potential terrorism

The U.S. State Department announced this year a revamp of its travel advisories-warnings page, which some had found confusing in past years. The new look includes a color-coded map with seven different advisories, from “Exercise normal precautions” (beige) to “Do not travel” (red).

The State Department can’t prevent you from going to a potentially dangerous place but it can provide you with plenty of good reasons to avoid them, and these are listed in its country information section. Afghanistan, for instance, is on the no-go list because of crime, terrorism, civil unrest and armed conflict with specific mention of “kidnappings, hostage-taking, suicide bombings, widespread military combat operations, landmines, terrorist and insurgent attacks.” And that’s just a partial list.

The good news is the State Department’s site also provides tourists with practical advice on how to protect themselves from all kinds of threats like thieves (don’t flash cash) to angry crowds (steer clear of all demonstrations) and kidnappings (don’t travel in certain routes or neighborhoods after dark). The State Department also has a travel-safety program called STEP (Smart Traveler Enrollment Program) and you can enroll on the same site.

4. The threat of diseases, viruses

A quick visit to the Travelers’ Health page at the U.S. Centers for Disease Control and Prevention website shows which countries are dealing with outbreaks of malaria, yellow fever, rabies and the Zika virus. Learn how they are transmitted and spread, how to protect yourself and where to find clinics for treatment. The CDC also provides recommended vaccinations for countries around the world as well as a host of stay-healthy-while-traveling tips.

5. The threat of potentially unsafe airlines

This is something most of us will never, ever have to worry about but here goes: The Europe Union Air Safety Committee updates a list of carriers around the world that are banned from operating within the European Union “for failure to adhere to the applicable international safety standards.” Although officially called the air safety list, most know it as the E.U.’s blacklist, and you can see the complete list here.

Most of the airlines on it are smaller regional carriers from Asia, Africa, the Middle East and one from South America. The list is publicized, according to its website, so those who travel outside the European Union — where the ban does not apply — can “avoid traveling with these airlines.”

Do banned airlines ever get off the list? Yes, and here’s the explanation from the E.U. air travel site: “The Commission’s sole aim is to improve aviation safety, which is in everyone’s interest, and in no way to affect a country’s economic or social development. Countries affected can put in place technical assistance measures to help airlines achieve a satisfactory level of aviation safety. Moreover, the Commission is always ready to explore any possible way of cooperating with countries which show a genuine intention of addressing their shortcomings with regard to aviation safety.”

Finally, millions and millions of us travel safely each and every day with no threats to worry about whatsoever. Well, unless you count the threat of an airline’s losing your bag, but that’s why I only travel with a carry-on, a bag that doesn’t leave your side.

Rick Seaney is the CEO of FareCompare, a website that curates the best deals on flights from around the world. Any opinions expressed in this column are solely those of the author.