After the announcement on May 19 by the European Union that vaccinated Americans can soon travel to Europe, the masterpieces of the Louvre and the beaches of Sicily once again feel within reach. Here are six things to know if you’re planning a trip to Europe this summer.

Flight schedules will be in flux for months to come

Because the United States currently remains closed off to international leisure travelers, making the upcoming travel between the two continents one-sided for now, aviation-industry experts say there won’t be a massive surge in Europe-bound flights from the United States this summer.

The E.U. announcement is a “welcome development” for American travelers, said John Grant, a senior aviation analyst at OAG, a travel data and insight provider. “However, airlines require traffic from both ends of the route to operate sustainable services.”

Until the U.S. borders reopen to European tourists, Mr. Grant added, “the situation remains broadly unchanged for the airlines.”

On May 10, according to OAG data, airline schedules showed fewer than 2.5 million seats on flights heading from the United States to Western Europe in July. By contrast, more than 4.5 million flight seats went from the United States to Europe in July 2019.

Still, in the coming weeks, airlines will introduce new routes and resume paused service, first to countries that have, independently of the E.U. announcement, already started welcoming vaccinated Americans. American Airlines, Delta Air Lines and United Airlines are either starting or resuming routes to Greece. Delta and United will launch nonstop service from New York City to Dubrovnik, Croatia, in early July. Delta restarted service to Iceland in mid-May, and United will begin flying from Chicago to Reykjavik on July 1.

Additionally, United plans to resume flights to Spain and Portugal in July, Air France has tentatively scheduled the launch of its Denver-Paris route for July 2 and JetBlue will start its first-ever trans-Atlantic route, from New York City to London, on August 11.

Flight schedules are almost certain to change as summer rolls on. According to Transportation Department rules, if an airline cancels or significantly changes a flight, passengers are entitled to cash refunds.

A good bet, Mr. Grant said, is to “look first at travel to those cities with a high frequency of service, perhaps at least twice daily, since those destinations with just one daily flight or less than daily services are likely to be the more vulnerable services for short notice cancellations.”

For those who decide to proactively bow out of a trip, most airlines, including American, United, Delta and Air France, are continuing to waive most change fees for classes above Basic Economy, although the fare difference would apply.

Onboard, you’ll brush elbows with strangers, but you won’t go hungry.

Daily passenger numbers have been generally inching upward, according to the latest Transportation Security Administration stats, and long gone are the days of empty planes and blocked middle seats. Delta, the final holdout, stopped the practice in early May.

Serving food and drinks, which most airlines paused or scaled back in some way last year, is also back, and many other elements of flying will feel similar to how it did before the pandemic. Yes, Air France is still serving fresh bread, wine and cheese, but there are also zeitgeist-y new flourishes to look forward to on other airlines, including spiked seltzers from Truly offered on American and White Claw on United.

Certain pandemic-era changes designed to minimize touch-points persist. To keep the aisles and galleys clear, many airlines are now asking passengers to wait for the “vacant” light before walking to the restrooms. In Delta One business class, pre-meal drinks have been eliminated, and beverages will come with meals. Delta has also introduced tap-to-pay technology for onboard extras. But even on planes where contactless payments are not available, keep a credit card within reach: Many airlines don’t accept cash.

Finally, although mask mandates are loosening in certain areas of the United States, particularly for vaccinated people, passengers ages 2 and up are still required by law to wear masks on planes and in airports.

Hotel flexibility will vary, so read the fine print

By now, most of the large American-run chains have reverted to their pre-Covid cancellation policies for reservations made before a certain date (that has come and gone), and for travel through a certain date (that has come and gone). But some companies are still being flexible: Hilton has always had generous cancellation policies, and Four Seasons has been consistently easy about changes and cancellations during the pandemic.

Travel-industry insiders also have noticed flexibility among independent hoteliers.

“We’ve felt that small, family-run luxury properties are actually more nimble than some of the big hotel chains,” said Louisa Gehring, the owner of Gehring Travel, an affiliate of Brownell, a Virtuoso luxury travel agency. “Rather than lay off all their employees or point to an overarching corporate cancellation policy, they’ve had flexibility to keep the teams on, work with clients on a case-by-case basis and really step up to the plate.”

Policies vary by property, she added, but even some of the more rigid ones now include exceptions for Covid.

One thing to watch for is the credits-versus-refunds flash point: Even in cases when a hotel won’t swallow a deposit or prepayment outright, will you get a cash refund or will you be asked to rebook? Last year, Greece and Italy both passed laws allowing hotels and other travel companies to issue credits, rather than cash refunds, for canceled bookings. Although vaccines, the eagerness to travel and pandemic fatigue may make the idea of a credit less odious than it seemed last spring, always ask about policy specifics, including blackout and expiration dates.

Realize that Paris won’t look exactly like the Paris you remember

The Palace of Versailles is open and President Emmanuel Macron is sipping espresso outside Parisian cafes, but nightclubs will remain closed even after France’s countrywide curfew ends in June. At restaurants and bars in Madrid, groups are capped at four people inside and six people outside. Germany and the Netherlands remain closed to American tourists.

“Clearly, we will not come back to ‘normal’ straight away, and travelers will have to be conscious of health measures and respect rules at the destination,” said Eduardo Santander, the executive director of the European Travel Commission, a Brussels-based nonprofit that represents the national tourism boards across the continent. “We all — destinations, businesses and guests — cannot let the guard down too soon both for our own health and for the safety of people around.”

In short, any trip to Europe this summer will come down to managing expectations.

“Save the ‘must check all the boxes’ trip to Europe for a bit later, once all new protocol kinks have smoothed out,” Ms. Gehring said. But you may still have an unforgettable experience regardless.

“Travel is not a right; it’s a privilege, as we’ve all learned,” Ms. Gehring said. “Speaking Spanish with a local or eating homemade pizza in Naples — even if under new rules and restrictions — may elicit stronger feelings of joy and appreciation than expected.”

Prepare to schedule and commit, rather than wing it

Much like in the United States, most major European museums and attractions now require timed tickets in an effort to honor capacity limits and space out crowds.

That’s good news for anyone who hates waiting in line. But snapping a selfie with “The Mona Lisa” means planning. Timed tickets are usually nonrefundable and rain-or-shine.

Popular restaurants may also require advance reservations, especially for those committed to dining outside. Resy, which is owned by American Express, has expanded its international footprint over the past year; travelers can use the app or website to book top restaurants in the United Kingdom and around mainland Europe.

In previous years, Europe’s excellent rail system and inexpensive regional airlines made it easy to wake up in one country and decide, a few hours later, to visit another. Though that spontaneity might still seem appealing, there are also advantages to staying put.

“Instead of a breakneck itinerary that may include three days in London, three in Paris and five nights between Rome and Tuscany, a true deep-dive into one country allows for greater flexibility and less room for disappointment,” Ms. Gehring said. “Having four nights in Florence instead of two gives you twice as many chances to get that timed ticket at The Uffizi.”

Update your tech and tap into tech updates

Researching restaurant reservations and booking timed tickets could require either a good data plan, Wi-Fi or both. If it’s been a while since you’ve taken your phone overseas, research your wireless provider’s options so you are not slapped with expensive roaming charges. Several companies, including Verizon Wireless and T-Mobile, have per-diem travel passes that include unlimited data and texting, and certain calling benefits, in Europe. Or, just stick to free Wi-Fi. And be sure to bring a portable charger — many tickets and entry passes are digital.

Also take stock of the technology that has adapted alongside the pandemic, and how it can make traveling easier — and perhaps even a bit more enjoyable.

Uber Reserve, which launched in November and has recently expanded to London, Paris and elsewhere in Europe, allows users to schedule rides up to 30 days in advance. Uber Rent, also available in Europe, allows users to book rental cars from companies like Avis.

There are also several new travel-friendly bells and whistles from Google Maps. Updates set to be rolled out to Live View, the app’s augmented-reality mode, include overlaid street signs at difficult-to-navigate intersections. The app has also recently introduced more tailored maps that “know” when a user is at home or traveling: A London vacationer who fires up the app at noon, for instance, will see nearby lunch options as well as local tourist attractions.

Sarah Firshein is a Brooklyn-based writer. She is also our Tripped Up columnist. If you need advice about a best-laid travel plan that went awry, send an email to travel@nytimes.com.

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