These 7 island destinations feel a world away from home, but you don’t need a U.S. passport to visit them

From the Florida Keys to Guam, these islands offer different versions of an island getaway. (Westend61 via Getty Images)An island vacation can take you far from home, but for Americans, getting there doesn't always require a passport. Several tropical and subtropical islands are part of the United States or its territories, giving U.S. citizens the chance to visit sandy beaches, crystal-clear waters and laid-back towns without technically leaving the country.

Some are familiar vacation spots, like the Florida Keys and Puerto Rico, and others take you farther afield. The U.S. Virgin Islands offers a trio of easy Caribbean escapes, while Guam puts remote Pacific landscapes within reach if you're willing to make the journey.

Depending on the destination, there are several logistics to keep in mind. Certain U.S. territories require proof of citizenship or other documentation. Routing matters too, because connecting through a foreign country requires a passport even when the final destination does not. So double-check the details before you go.

Puerto Rico has it all: historic cities, surf towns, rainforest and more.

Puerto Rico is an easy flight from the East Coast, with direct routes from New York, Boston, D.C., Miami and other major markets. There's a lot to like here, including Caribbean beaches, tropical rainforests, centuries of history and one of the region's best food scenes.

It's impossible to cover everything in one visit, but first-timers should start in Old San Juan, where colorful buildings and cobblestone streets lead to formidable Spanish forts and something delicious to eat around every corner.

If you have more time, head to Rincon on the west coast for a more laid-back vibe that trades high-rise hotels for quaint town squares, art markets and legendary surf spots like Domes Beach. Or head east to hike among waterfalls and lush landscapes in El Yunque National Forest. If you want to leave this island for an even smaller one, take a ferry or a short flight to Culebra and stroll along the white sands of Flamenco Beach.

Looking for a mix of beach life, history and outdoor adventure? Head to St. Croix.

St. Croix is the largest of the U.S. Virgin Islands. Cane Bay Beach on the north shore has stunning coral reefs (and dive shops that can outfit you with snorkel or scuba gear), while Sandy Point National Wildlife Refuge protects a two-mile stretch of quiet sand that draws nesting sea turtles (just note the beach closes to the public roughly mid-April through August).

Christiansted is a good home base if you want easy access to restaurants and shops. It's dotted with Danish colonial architecture, most noticeable in the many pastel exteriors and the official government buildings constructed with the yellow bricks that Danish ships once used as ballast. Leave time for a day trip to Buck Island Reef National Monument. It's located just offshore and surrounded by a coral reef that you can view through your snorkel mask on a guided tour.

Over on the island's west coast, Frederiksted, aka "Freedom City," is the site of the 1848 emancipation that freed enslaved people in the Danish West Indies. Tour the mid-1700s Fort Frederik, then head north to Rhythms at Rainbow Beach for some coconut shrimp and live music, or check out the Cruzan Rum Distillery for a tour and tasting.

The second largest of the U.S. Virgin Islands is a great place to hike, whether that's along an actual trail or up the famous 99 Steps.

St. Thomas is a great choice for travelers who want a relaxing beach vacation with name-brand resorts. It's popular with shoppers who take advantage of duty-free allowances, and each night, visitors flock to the patio at Sunset Grille for beautiful sunsets, rum drinks and whole snapper.

Magens Bay is the island's best-known beach, with white sands, calm waters and rentable cabanas. Pair some R&R with a hike along the Discovery Nature Trail, where you can traverse through multiple ecosystems, including forest and mangrove habitats.

In Charlotte Amalie, get a glimpse into the island's Danish past via its multi-colored buildings and Fort Christian, a bright-red 17th-century fort that's the oldest standing structure in the USVI. Then climb the famous 99 Steps, another remnant of the island's Danish heritage, which takes you up to a historic watch tower known as Blackbeard's Castle. Visitors can also take the Skyride tram to Paradise Point for sweeping harbor views from approximately 700 feet above sea level. When you're ready for a break, order a Bushwacker cocktail, a St. Thomas original that tastes like a boozy milkshake.

Despite their proximity to the mainland, the Keys feel like they're a world away.

The Keys stretch for 125 miles below the mainland and are accessible via the aptly named and very scenic Overseas Highway. The Upper Keys include Key Largo, which is a natural starting point on any southbound adventure, especially if you like snorkeling and diving.

From there, Islamorada offers guided charters showcasing its reputation as the sportfishing capital of the world, and Marathon pairs laid-back beaches with marine-life experiences. Get up close and personal with dolphins at the Dolphin Research Center, and meet some rehabbing sea turtles at the Turtle Hospital.

Keep going, and you'll eventually hit Key West, where casual seafood restaurants and lively bars make this island a popular stop with sun-seekers and Hemingway fans (the writer lived here in the 1930s, and his old house is now a museum). If you want to get even more remote, take a ferry or seaplane about 70 miles west to Dry Tortugas National Park, where you can tour Fort Jefferson and snorkel along the coral reefs just offshore.

If your travels bring you to St. Thomas, take the ferry to St. John for an even quieter escape.

St. John is just 20 square miles and has no airport, so most visitors fly into St. Thomas and take a ferry over. Much of the island lies within the protected Virgin Islands National Park, which gives it a less-developed feel and lots of opportunities to hike, swim and spend entire days hopping between beaches.

Trunk Bay is a stunner, with white sands, turquoise waters and a snorkeling trail with informative underwater plaques about the area's marine life. When you're ready to rejoin civilization, Cruz Bay has restaurants and bars slinging local specialties like conch fritters and johnnycakes.

This collection of postcard islands is an obvious choice for Americans who want to get far from home without leaving the country.

Few places let you pack so much variety into one trip. Oahu pairs Waikiki's beaches with Honolulu's restaurants, nightlife and cultural attractions, including the Pearl Harbor National Memorial, while Maui offers luxe resorts and the winding Road to Hana.

Kauai is known as the "Garden Isle" and is incredibly lush, so it's the perfect backdrop for hiking and helicopter rides. And the Big Island has a little bit of everything, from black sand beaches to the Hawaii Volcanoes National Park.

There's so much to do in Hawaii that many visitors stick to one island, but if you want to hop around, there are lots of local flights between islands.

Guam may take much longer to get to, but you'll be rewarded with stunning beaches and sunsets.

This tropical Pacific island is known for its beautiful beaches and clear waters, perfect for snorkeling and diving. Tumon Bay is the island's tourism hub, with resorts dotting the coastline. You'll also find plenty of shops and restaurants, plus outfitters who will get you equipped for diving among the reefs and historic wrecks.

Beyond the beach, Two Lovers Point offers sweeping views over the coastline and is a popular spot to watch the sunset. And you shouldn't leave without sampling red rice, ceviche-like kelaguen and other Chamorro (also spelled CHamoru) cuisine, which blends Indigenous foods with Spanish, Asian and American influences.

As long as your itinerary goes through Honolulu without a stop in a foreign country, U.S. citizens don't need a passport to visit Guam. Travelers visiting without one should bring an original or certified copy of a U.S. birth certificate, along with a valid federal photo ID or REAL ID-compliant state-issued photo ID.