Boat rides in the Thung Nham eco-tourism zone take visitors up close to glowing stalactites and several bird species.
The Trang An Landscape Complex, a UNESCO World Heritage site, is a site of poetic beauty.
The Thung Nham ecotourism zone within the complex is situated in Ninh Hai Commune, Hoa Lu District, about 12 km from the center of Ninh Binh Town, the northern province of Ninh Binh.
Entrance tickets to this ecotourism zone costs VND100,000 ($4.3) for adults; VND50,000 ($2.1) for children between 0.8 - 1.3m tall. Visitors have to pay extra if they want a boat ride. 
But Cave is said to be one of the most beautiful natural water caves in Vietnam. For VND20,000 (86 US cents) per turn, visitors will be taken in a boat along the length of nearly 500 meters of the cave, holding their own flashlights to focus on whatever feature interests them.
The featured attractions here include a jelly stone block shaped like a Vietnamese deity from folk tales and many natural stalactites that glow in the dark. The flashlight is provided by the boat driver.
A boat journey in the Thung Nham ecotourism zone takes visitors to many spectacular places like a bird park, a mermaid cave, an orchard, the But Cave, and the Vai Gioi Cave.
At around 5-6 p.m, thousands of birds of different species, including some rare ones,return to their nests in the bird park.
While there are options to rent a bicycle and even take a walk through this park, the best way is a boat trip that costs VND30,000 ($1.3) per person.
Fish are plentiful in Thung Nham, and they are food for about 50,000 birds of 46 species that have nests in the park. Among these are two rare birds listed in the red book - flamingo and phoenix. 
Inland caves in the area that attract many explorers include Mermaid, Thuy Cung, Ba Co and Vai Gioi. 
The Thung Nham Ecotourism Zone is a great place to enjoy a bicycle ride. It has amenities that make it suitable for all visitors, couples, families, travel groups and companies. Some people who travel during the day bring along their own food to save time and money. However, it is better to come lightly packed for riding boats, walking and cycling.
One of the local specialties is mountain goat.
From Ha Noi, visitors can reach Ninh Binh by car, bus, train or motorbikes. From the Ninh Binh bus or train station, visitors can take a taxi to Thung Nham for VND130,000 - 150,000 ($6-6.5) A motorbike can be rented for VND150,000 a day.
Photos by Phong Vinh
