7 Best Sights in Halong Bay and North-Central Vietnam, Vietnam

Home to 32 species of mammals, including the endangered white-headed langur monkey, which lives among the jungle terrain and freshwater lakes, Cat Ba National Park covers about 263 square km (101 square miles) of Cat Ba Island. Within its tropical rain forest are 78 species of birds and 20 species of reptiles. In addition to impressive beaches and mangroves, within its boundaries are two historical caves once used as clinics during the Vietnam War. Signs outside the park offer four hiking routes; 1, 2, and 3 cost 40,000d, and 4, the Cang Viet Hai Trail, costs 80,000d. Active travelers can tackle this demanding (yet rewarding) 18-km (11-mile) trail across the park if they arrive before 10 am. For a striking vista of the surrounding scenery, the view from the park's observation tower is hard to beat. Be warned, though, the climb-up metal ladders and cliffs are not for the faint of heart. The park is about 30 minutes from Cat Ba Town.

Established in 1962 by President Ho Chi Minh, Cuc Phuong National Park is Vietnam's oldest national park. Cuc Phuong consists of 220 square km (85 square miles) of heavily forested subtropical lowlands sheltering 97 mammal species, including nine species of civet, a kind of barking deer called the muntjac, as well as the extremely rare Delacour's langur. Approximately 336 bird species and 76 types of reptiles and amphibians live here as well, along with nearly 2,000 species of flora.

The Endangered Primate Rescue Center, which can be visited with staff accompaniment, focuses its rescue efforts on channels of illegal trade, then tries to establish populations in captivity. Although Cuc Phuong's habitat would seem to be the perfect place to see Vietnam's wildlife in full splendor, mammal- and bird-watching are sadly not particularly successful pastimes in the park. Despite Cuc Phuong's status as a protected preserve, the primary forest habitat has been heavily denuded during the past few decades, and officials believe the park's wildlife numbers are dwindling due to increased hunting and high tourism pressures, which have led to the creation of in-park facilities, hiking trails, and paved roads.

Despite the misfortunes of northern Vietnam's animals, Cuc Phuong is quite beautiful. In April, it's particularly lovely with swarms of butterflies. Dozens of miles of trails lead to such highlights as cascading Giao Thuy waterfall, a 1,000-year-old tree, and Con Moong Cave—the "cave of early man"—where evidence of prehistoric humans has been discovered. Longer hikes lead to some Muong villages. Many trails are well marked, but exploring this thick forest would be foolish without a guide. Be sure to bring lots of mosquito repellent, especially if you plan to stay the night.

One of the most intriguing sights on Cat Ba Island, Hospital Cave served as a bomb-proof medical facility during the American War. It also provided well-hidden refuge for Vietcong leaders and fighters during the conflict. Like Cu Chi Tunnels in the south and Vinh Moc Tunnels near Dong Ha, Hospital Cave is a prime example of the Communists' engineering ingenuity. Built between 1963 and 1965, the three-story facility is a labyrinth of dim chambers. Guides operate from outside the cave, which is around 10 km (6 miles) north of Cat Ba Town and will show you around the 17 rooms and point out notable features such as the old operating theater and a natural cavern that was used as a movie theater.

Although it is technically and geologically an extension of Halong Bay, the 300 or so karst islands of Lan Ha Bay feel somewhat removed from tourist traffic. Lying south and east of Cat Ba Town, they are too distant for most of the tour boats that leave from Halong City to reach. Therefore visitors here, mostly on itineraries arranged in Cat Ba Town, can enjoy the sense of peace and isolation that Halong Bay has arguably lost. Sailing, snorkeling, and kayaking are popular activities here. Lan Ha Bay also possesses several idyllic beaches such as Hai Pai Beach (also known as Tiger Beach), and day tours are cheap, starting at 360,000d.

It took 24 years (from 1875 to 1898) to build Phat Diem Cathedral, a complex comprising a lake, a cathedral, a stone church, Phuong Dinh (bell house), and three artificial grottoes. The cathedral, a hulking edifice made of local stone and hardwood, was designed by a Vietnamese priest named Father Sau, who died the same year the cathedral was completed. He is now interred in the narrow courtyard behind the bell tower, which was immortalized by Graham Greene in a description of a battle that took place here between French and Vietnamese forces in The Quiet American. The third floor of this tower supports a two-ton bronze bell that purportedly can be heard from 10 km (6 miles) away. The cathedral is flanked on both sides by four small chapels, all built in the late 19th century and dedicated to various saints. The prayer hall is a wooden marvel; almost the entire interior is made of Vietnamese ironwood, with 48 massive pillars supporting arched ceiling beams in what is truly an artist's loving creation. The curved eaves are a nod to Sino-Vietnamese architecture, but the crosses and saints (all sitting in the lotus position) reflect the fervor of the 150,000-strong congregation. Many of Phat Diem's Catholics fled to the south in 1954 when Vietnam was divided. A great deal of restoration work has been done on the complex, which was bombed heavily by American B-52s in 1972.

Catholicism has experienced a comeback in these parts, and because a more liberal tone has been adopted toward religion by Hanoi, Sunday Mass is now extremely popular. Services are held at 5 and 9 am, and by 10 everyone's already out in the fields. On holidays such as Christmas and Easter, expect crowds of 10,000 or more.

Closer to Ninh Binh city than Tam Coc, UNESCO World Heritage-listed Trang An offers a very similar experience to its more famous near neighbor. Although it is very popular with Vietnamese tourists, most visitors find it less crowded and more hassle-free than Tam Coc. Boat trips leave from the garish main office and take around 2½ hours, although the ticket operators will ask if you would like the 2-hour "short" tour instead. Boats will depart when they have four passengers. The journey by rowboat takes you through nine caves, some of which are very low and twisting, and along beautiful waterways lined with limestone karst. The landscape is of high historic and archaeological importance. Several pagodas can be visited on the boat tours, while the highest altitude caves dotted around the area have archaeological traces of human activity dating back almost 30,000 years. Unfortunately, it is not yet possible for visitors to access these higher altitude caves. Your boat operator will ask if you would like to stop and view the pagodas, and you can opt-in or -out (but if you say yes, the rower's arms will get a break). There are bathrooms at these small stops, and using them costs 2,000d. There has been increasing pressure put on these rowers to deliver good customer service, so don't be surprised when they hand you a survey to indicate your opinion of the tour. Tips are not mandated but still appreciated.

If you're already in Ninh Binh, there is no need to book a reservation for any of the boat trips. Just show up and hop on!