10 must-see natural phenomena around the world
From the tropical paradise of Cook Island to the rolling greenery of the Scottish Highlands, your travel bucket list is ever expanding. But we suggest you add a little wiggle room in your itinerary for some of these you-have-to-see-it-to-believe-it sites. Pink lakes, sherbet-colored mountains and glowing beaches—this planet is an amazing place. But make plans to see these wonders soon, before they disappear.
Great Blue Hole (Belize, City Belize)
If you couldn’t tell by its name, the Great Blue Hole is a giant underwater hole in the middle of Lighthouse Reef, 73 miles off the coast of Belize. Technically, it’s a sinkhole that formed as far back as 153,000 years ago, before sea levels were as high as they are today. After some glaciers danced around and melted, oceans rose and filled in the hole. The near-perfect circle is 1,043 feet in diameter and 407 feet deep, giving it a dark navy hue. Not only is the Great Blue Hole a World Heritage Site of UNESCO, but it was also one of Jacques Cousteau’s top diving spots, so you know it’s legit. You’ve got to be an expert scuba diver to actually go down into the hole, but snorkeling on its edges is allowed (and frankly offers more colorful scenes of fish and coral due to the sunlight). But, if you want the best view? Hop on a helicopter for a visually stunning flyover tour.
Salar De Uyuni (Potosí, Bolivia)
In the mood for something savory? How about 4,086 square miles of salt? That’s how big Salar de Uyuni, the world’s largest salt flat, is. Located in southwest Bolivia, near the Andes Mountains, this bright white, flat expanse looks like a desert but is actually a lake. Let us explain: Roughly 30,000 years ago, this area of South America was covered in a giant saltwater lake. When it evaporated, it left behind a thick, salty crust on the earth’s surface. Today, the flat produces salt and half the world’s lithium. During the rainy season (December through April), smaller surrounding lakes overflow and cover Salar De Uyuni in a thin, still layer of water that reflects the sky almost perfectly for a sublime optical illusion. If your goal is seeing as much of the flat as possible, head out during the drier season (May through November). Tours are available from starting points in both Chile and Bolivia. Just be sure to hydrate.
Mud Volcanoes (Azerbaijan)
Nestled between Eastern Europe and Western Asia is the Republic of Azerbaijan, home to hundreds of volcanoes that regularly spew goopy, gray mud. These short volcanoes (10 feet tall or so) dot the desert landscape throughout Gobustan National Park (another UNESCO World Heritage site) near the Caspian Sea. Since eruptions are caused by gases escaping through the earth instead of magma, the mud tends to be cool or even cold to the touch. Don’t be afraid to join in if other visitors bathe in the mud, which has been used for skin and joint ailments and in pharmacology. Certainly not FDA-approved, but when in Azerbaijan, right?
Vaadhoo Island (Maldives)
After taking a dunk in Azerbaijan’s volcanic mud, we recommend bathing in glow-in-the-dark ocean water on the tiny tropical island Vaadhoo. Visitors can see the ocean shores light up at night due to tiny phytoplankton in the water. These bioluminescent buggers emit a bright light when the water around them hits oxygen (aka, waves hitting the beach) as a defense against predators. Lucky for us, this creates a naturally occurring liquid glitter we can swim in. Consistently ranked one of the top vacation spots in the world, the Maldives is also increasing in popularity because it’s sadly disappearing. About 100 of the 2,000 islands that make up the Maldives have eroded in recent years and water levels continue to chip away at many of them. Might be time to move this item up on your bucket list.
National Science Foundation/Peter Rejcek/Wikipedia
Blood Falls (Victoria Land, East Antarctica)
There are a bajillion beautiful waterfalls to see around the world before you die (or they dry up), but Blood Falls in east Antarctica is one of a kind for its blood-like, well, flow. Explorers discovered the red-hued river flowing off the Taylor Glacier in 1911, but it wasn’t until last year that we figured why exactly the water was red. Turns out, there’s iron in the water (from an underground lake) that oxidizes as it hits the air. It’s tricky to get to Antarctica, yes, but certainly worth the trip to see this five-story-tall phenomenon in person.
Lake Natron (Arusha, Tanzania)
If you’re dying to see naturally occurring red water but aren’t partial to Antarctica’s chill, Lake Natron in Tanzania is a hot option. Salty water, high alkalinity and shallow depths pretty much make Lake Natron a warm pool of brine only microorganisms could love—and love it they do. During photosynthesis, the lake’s microorganism population turns the water a bright reddish-orange. Since the lake is no fun for large African predators, the setting makes a perfect annual breeding ground for 2.5 million lesser flamingos, a species listed as “near threatened.” So get there quickly. And kiss a flamingo for us.
Monarch Butterfly Biosphere Reserve (Michoacán, Mexico)
This entry on our list isn’t so much about a particular location as it is about what happens there. Every fall, monarch butterflies begin a 2,500-mile migration from Canada to Mexico. Over 100 million butterflies travel together, turning the skies orange and black, down through the U.S., before settling in central Mexico. Once they’ve reached hot spots like the Monarch Butterfly Biosphere Reserve, about 62 miles outside Mexico City, they nest, essentially taking over every square inch they can find. Pine trees literally sag with the weight of hundreds of butterflies latching onto branches. Visiting in January and February is best, when the populations are highest right before the butterflies head north in March. Fun fact: The monarchs that make it back to Canada in spring are the great-great-grandchildren of the butterflies that lived it up in Mexico over the winter. Unfortunately, the monarch population has dwindled significantly in the past 20 years, due in part to shrinking milkweed availability, the monarch’s favorite food.
Jeju Volcanic Island and Lava Tubes (South Korea)
For spelunking enthusiasts, Jeju Island is a must-see. Located 80 miles off the southern tip of South Korea, the 1,147-square-foot island is essentially one big dormant volcano with hundreds of tinier volcanoes around it. Most notably, however, is the Geomunoreum Lava Tube System below Jeju’s surface. An enormous system of 200 underground tunnels and caves formed by lava flows between 100,000 to 300,000 years ago provide ample space to pretend you’re Lara Croft. Did we mention many of these caves have multiple levels? And there’s a lake underground, too? With some of the longest—and largest—caves in the world, it’s no surprise this is another UNESCO World Heritage Site on our list.
Ma Mingfei/Getty Images
Zhangye Danxia Landform Geological Park (Gansu, China)
There’s really no other way to describe these mountains than as orange sherbet rocks. The Zhangye Danxia Landform Geological Park is mile after mile of brightly colored, striped hillside made of sandstone and mineral deposits. Formed over millions of years as tectonic plates shifted and pushed underlying rock to the earth’s surface, this—you guessed it—UNESCO World Heritage Site is a lesson in both geology and art. Similar rainbow-colored mountains can be found in Peru, but this range in China’s northern Gansu province is easier to hike and offers equally stunning views of red, orange, green and yellow stone. Visit between July and September for optimal sunshine and light.
Federico Fioravanti/Getty Images
Cascate del Mulino (Saturnia, Italy)
Volcanic activity heats water below the earth’s surface, creating either boiling geysers or calm, steamy, natural hot tubs. We’ll take option #2. While there are many places to experience the soothing properties of hot springs (Blue Lagoon, Iceland; Khir Ganga, India; Champagne Pool, New Zealand), and we highly recommend you get to at least one in your lifetime, the Cascate del Mulino springs in Saturnia, Italy, caught our attention. Formed naturally by a sulphurous waterfall carving its way through rock, this sprawling landscape of pools clocks in at 98° F and is constantly flowing. The water is said to have healing properties thanks to sulfur and plankton swirling around. The best part? Cascate del Mulino is free to swim in and open 24/7. If you’re in the mood for a more upscale Tuscan hot springs vacay, stay at the Terme di Saturnia, a spa and hotel situated closer to the hot springs’ source.
On March 19, 2020, United operated its first flight carrying cargo without passengers on board. While the passenger cabin was empty, its cargo hold was completely full, carrying more than 29,000 pounds of commodities from Chicago O'Hare International Airport (ORD) to Frankfurt Airport (FRA).
A year later, United Cargo has operated more than 11,000 cargo-only flights carrying more than 570 million pounds of freight. To support the COVID-19 pandemic recovery efforts, United Cargo has also transported more than 113 million pounds of medical and pharmaceutical products on both cargo-only and passenger flights as well as approximately 10 million COVID-19 vaccines, providing global communities access to the items they have needed most.
"At the beginning of the pandemic, we knew we were uniquely positioned to utilize our widebody aircraft and our network to keep commodities moving, so we quickly mobilized various departments throughout the airline to launch a cargo-only network of flights that would keep commodities moving," said United Cargo President Jan Krems. "Thanks to those efforts, United Cargo has delivered millions of items to countries all around the world. We would not have been successful without the steadfast support of our employees, industry partners and our customers."
Since last March, United Cargo has transported almost 850 million pounds of freight on cargo-only and passenger flights. The airline will continue to monitor market trends adjust its cargo-only flight schedules to help ensure we are meeting our customer's evolving shipping needs.
Whether you haven't flown with us for a while or just need a quick refresher before your spring trip, read this list of tips to know before your flight and arrive at the airport travel-ready:
1. Download the United app for contactless bag check, travel assistance and more
Before your flight, download the United app to view your flight status, check in, sign up for flight notifications, locate departure gates, access our free personal device entertainment when available and more. We've also updated our app with new features that can make your trip a little safer, including contactless bag check.
Don't forget to use Agent on Demand for help with any and all questions you may have before your flight. This new capability is available at all our U.S. hub airports and allows you to use your own mobile device to contact a customer service agent via phone, video or chat to help with day-of-travel questions while you're at the airport. Learn more about Agent on Demand here.
2. Check out the Travel-Ready Center
Our Travel-Ready Center makes it easy to get a personalized overview of everything you need to do in preparation for your flight. Just enter your confirmation number or MileagePlus® number and you'll find detailed information on all the documents, tests and more that you'll need for your trip.
3. Read and sign the Ready-to-Fly checklist
Before completing check-in, all United travelers will need to read our Ready-to-Fly checklist and confirm that they understand and agree to our policies. These include:
Acknowledging that you haven't had any symptoms of COVID-19 in the last 14 days
Agreeing that you will not fly if you have tested positive for COVID-19 within the last 21 days
Confirming that you will follow all policies regarding face masks, social distancing and other health and safety measures we've adopted
4. Arrive early; avoid the stress
Airports can be busy, especially during peak travel periods like spring break season. The TSA advises arriving at the airport two hours before your flight for domestic travel and three hours for international travel in anticipation of long security lines. This can help ease the stress when navigating busy check-in areas, security lines and crowded boarding gates.
5. Get familiar with CleanPlus
United CleanPlus℠ is our commitment to delivering industry-leading cleanliness as we put health and safety at the forefront of your experience. We've teamed up with Clorox to redefine our cleaning and disinfection procedures and Cleveland Clinic to advise us on enhancing our cleaning and disinfection protocols, like:
Disinfecting high-touch areas on board and in the terminal
Using electrostatic spraying, Ultraviolet C lighting wands and more advanced measures to clean aircraft cabins before boarding
Redesigning our mobile app to allow for touchless check-in and contactless payment, along with enhanced travel assistance features
Implementing high-efficiency (HEPA) filters on our aircraft that completely recirculate cabin air every 2-3 minutes and remove 99.97% of airborne particles, including viruses and bacteria
Studies show COVID-19 exposure risk is minimal when air filtration systems and masks are in use, so you can rest assured that the steps we've taken to keep you safe truly make a difference.
6. Wear your mask
Federal law requires all travelers to wear a face mask in the airport, including customer service counters, airport lounges, gates and baggage claim, and on board during their entire flight. Make sure you review the requirements for face masks, including what an acceptable face mask looks like.
7. Get ready for a safer boarding process
To make boarding even safer, we now have travelers board their aircraft from back to front. At the gate, just listen for your row number to be called – we'll ask a few rows at a time to board, starting with the last row of the plane. This helps everyone maintain a safe distance from each other during boarding without slowing things down. As you step onto the plane, flight attendants will hand each passenger a sanitizing towelette, which you can use to wipe down your seat to ensure it's extra clean.
8. Pack smart
Before packing your bags, check to see what exactly you can carry on and what you should plan to check. You can also copy your confirmation number into our Baggage Calculator tool to learn about the bag allowance included with your reservation, as well as the cost of checking any additional bags.
9. Check your flight status, important notices and weather
Check the United app regularly for the latest updates on weather conditions, flight status, gate numbers and seat assignments. You can also visit our Important Notices page to find essential information and updates about travel waivers, international travel, TSA and security, airports and United Club locations.
10. Relax and enjoy your flight
Once you're on board, it's time to sit back and enjoy your flight. Our flight attendants will be happy to help you with anything else you need.
This week, we were honored to become the first U.S. airline to join the UNICEF Humanitarian Airfreight Initiative to combat the COVID-19 pandemic by transporting the vaccine and other critically needed supplies to underserved areas of the globe.
"We are committed to helping the global community in any way we can, and we all must work together to do our part to bring this health and humanitarian crisis to an end," said Director of Cargo Specialty Products Manu Jacobs.
We will leverage our expertise to transport these critical pharmaceutical and healthcare shipments around the world safely, efficiently and expediently. We are proud to partner with the United Nations to support this global effort and provide equitable access to COVID-19 vaccines.
Together, we are facing an unprecedented challenge. United Together, we rise to meet that challenge.
Calling all AvGeeks and travelers! Take your next video call from a United Polaris® seat, the cockpit or cruising altitude with United-themed backgrounds for use on Zoom and Microsoft Teams.
Newly added to our collection is a background encouraging our employees and customers to vote. Our mission is to connect people and unite the world — and one of the most important ways to do that is to engage in the democratic process. No matter which party you support, we know our democracy will be stronger if you make your voice heard and vote.
So for your next meeting or catch up with friends and family, download the app to either your computer or mobile device to get started.
To use on Zoom:
- Start here by downloading your favorite United image to your computer or mobile device. Just click "download" in the bottom left corner of the image.
- Next go to your Zoom app (you'll need to download the app to access backgrounds) and click on the arrow to the right of your video camera icon in the bottom of the screen.
- From here select, "choose virtual background" to upload your uniquely United photo.
To use on Microsoft Teams:
- Start by downloading your favorite United image to your computer. Just click "download" in the bottom left corner of the image.
- If you're using a PC, copy the image you want to use into this folder:
- C:\[insert your device user name here]\AppData\Microsoft\Teams\Backgrounds\Uploads
- If you're using a Mac copy the images to this folder on your computer:
- /users/<username>/Library/Application Support/Microsoft/Teams/Backgrounds/Uploads
- If you're using a PC, copy the image you want to use into this folder:
- Once you start a Teams meeting, click the "…" in the menu bar and select "Show background effects" and your image should be there
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This is why we fly.
20 UCSF Health workers, who voluntarily set aside their own lives to help save lives, are on their way to New York City.
We are humbled by your selfless sacrifice.
In celebration and appreciation of all first responders and essential workers. 👏🏻👏🏼👏🏽👏🏾👏🏿
This is the story of Jason and Shantel. You see, Jason and Shantel love each other very much. They also love traveling and they love the classic Adam Sandler film, The Wedding Singer.
It all began when Jason reached out to United's social media team, hoping for assistance with his upcoming plan to propose. Some phone calls and one borrowed guitar later, the stage was set for Jason. Put all that together, mix in some helpful United employees and, voila, you have a truly memorable marriage proposal. Congratulations to this fun-loving and happy couple, and here's to many more years of making beautiful music together.
A big thank you to Chicago-based flight attendants Donna W., Marie M., Karen J. and Mark K. for making this proposal come to life.