Paradise Cave is one of the few sights in the park that can be visited independently. Photo © Dana Filek-Gibson.

The Caves of Phong Nha-Ke Bang National Park

A labyrinth of subterranean tunnels and jaw-dropping, otherworldly landscapes, Phong Nha-Ke Bang National Park may be off the beaten path for now, but its anonymity is fading fast. Decked out in eerie, alien rock formations and spindly stalactites, these tunnels are estimated at around 3-5 million years old. Here you’ll find the world’s largest cave, home to a thunderous river, clouds, and an entire jungle ecosystem.

The Imperial City Gate. Photo © Dana Filek-Gibson.

The Imperial City in Hue, Vietnam

From the early 19th century through the end of the Vietnamese monarchy in 1945, Hue’s Imperial City housed an impressive cache of temples, palaces, and administrative buildings. Of the 148 buildings in the walled Citadel complex, today 20 remain. Wide, opulent palaces and dimly lit temples pepper the now-overgrown grounds, boasting a mix of traditional Vietnamese architecture, vibrant lacquered woodwork, and ornate rooftops, not to mention 143 years’ worth of imperial history.

Visitors gaze at a tumbling waterfall from an observation platform.

La Paz Waterfall Gardens, Costa Rica

Costa Rica’s splendid nature and wildlife park La Paz Waterfall Gardens at Montaña Azul features trails through a soaring hangar-size aviary with a separate climate-controlled butterfly cage. There’s also a hummingbird garden, a serpentarium (snakes), a walk-through ranarium (frogs), a monkey exhibit, plus a trout lake and orchid houses.

Stairs leading to an old building near Perfume Pagoda. Photo © Tuomas Lehtinen/123rf.

Day Trips From Hanoi

Beyond the city limits, Hanoi’s suburbs and surrounding countryside offer a few easygoing day trips. Take a jaunt to the booming traditional handicraft villages of Tam Coc and Hoa Lu, Ninh Binh’s main attractions, and visit the serene pagoda complex of the beautifully austere Perfume Pagoda.

The mariposario (enclosed butterfly garden) at the Jardín Botánico del Quindío. Photo © Andrew Dier.

Colombia’s Jardín Botánico del Quindío

Outside the town of Armenia, the well-run Jardín Botánico del Quindío is home to hundreds of tree and plant species, many of which are threatened. Knowledgeable volunteer guides lead visitors on a mandatory 2.5-hour tour along jungle paths pointing out plants, trees, and birds visitors would otherwise miss.

Judy Arroyo with rescued sloths at the Sloth Sanctuary. Photo © Christopher P. Baker.

Costa Rica Nature Reserves: Puerto Limón to Cahuita

Nature reserves south of Puerto Limón in Colombia tend to be remote and undeveloped, making them perfect for adventure travel. The one exception is the world’s only sloth sanctuary, an education and research center based around rehabilitating rescued sloths that amounts to a highly-fulfilling experience for visitors.

Fire Ginger at Esquinas Rainforest Lodge in Piedras Blancas National Park, Costa Rica.

All About Piedras Blancas National Park, Costa Rica

Centered on the village of La Gamba, Piedras Blancas National Park was split from Parque Nacional Corcovado in 1999. The rainforest has no shortages of unique plants to admire, wildlife to watch, and plenty of other ways to spend your time. Here are suggestions for your visit, along with the best places to stay.

Vieques features miles of deserted beaches and bright blue water. Photo © Suzanne Van Atten.

The Electric-Blue Waters of Mosquito Bay

In 2013, Vieques’ world-renown bioluminescent Mosquito Bay went dark. Through continuing preservation efforts, the electric-blue glow of the lagoon has returned. Learn what makes the bay glow, what Puerto Rico is doing to keep it healthy, and what to expect from the magical and unique experience of seeing it for yourself.

Bone fragments found at the Marco Gonzalez Maya Site. Photo © Lebawit Lily Girma.

The Marco Gonzalez Maya Site, Belize

Those looking for a little Mayan history on Ambergris Caye in Belize can find it at the Marco Gonzalez Maya Site. History and adventure buffs will enjoy private guided tours of this virgin site, currently under study, which was inhabited by the Maya for 1,600 years.

Castillo San Felipe del Morro. Photo © Suzanne Van Atten.

Old San Juan’s Two Historic Castillos

History buffs and especially those interested in military history should take time to explore Old San Juan’s two historic forts, Castillo San Felipe del Morro dating from 1539 and Castillo de San Cristóbal dating from 1634.