En Cave (Swallow Cave) is one of the largest natural caves in the world, located deep within Phong Nha-Ke Bang National Park in Quang Binh Province, Vietnam. With its massive geological fault line, En Cave stretches over 1.6 kilometers through a giant limestone block at the heart of the national park. There are three entrances to the cave, the most famous of which measures 120 meters high and 110 meters wide.

The cave traverses an entire mountain range, featuring entrances that reach heights of up to 110 meters. In some areas, the ceiling of the cave rises to 145 meters, and the widest section of the cave corridor spans up to 200 meters. Inside, a clear, winding stream flows, leading to Son Doong Cave.

Exploring En Cave typically requires a full day of climbing, which includes crossing the Ba Gian slope and passing through Ban Doong, the home of the Bru-Van Kieu people. En Cave has gained international recognition, appearing in major media such as National Geographic, The New York Times, Lonely Planet, Good Morning America, and notably in the Hollywood blockbuster "Pan - Welcome to Neverland" (2015) produced by Warner Bros.

Origin of the Name

En Cave gets its name from the thousands of swallows that use the cave as a nesting site during the season. Visitors can witness the impressive sight of these swallows returning in flocks each evening or early morning.

History of Discovery

The Arem people have known about En Cave for centuries, as their ancestors used it as a home. Traditionally a nomadic tribe, the Arem moved seasonally based on the availability of food sources from hunting and gathering. En Cave, located in the central area of Phong Nha-Ke Bang National Park—the Kingdom of Caves—features numerous swallow nests adorning the ceiling.

Due to their small and agile stature, the Arem have honed their climbing skills over time. They would cut strong tree branches and secure them in rock cavities, using rattan ropes to create natural rope ladders to access the cave ceiling. This technique has allowed them to catch swallows, which have been a vital source of food and nutrition for the Arem people.

Historically, a man's ability to climb the cave ceilings to catch swallows was seen as a prerequisite for marriage, demonstrating his capability to support a family. In recent years, with provincial support, the Arem have settled in permanent villages, abandoning their nomadic lifestyle. However, each June, they maintain the tradition of entering the caves to collect young swallows that have fallen from their nests while learning to fly, preserving their customs and cultural heritage.

In 1990, Ho Khanh discovered En Cave during a trip to find agarwood, but it wasn’t until 1994, after experts from the British-Vietnamese Cave Exploration Team surveyed the cave, that it gained widespread recognition.

Ban Doong

Ban Doong was established in 1992 by a group of Bru-Van Kieu people who relocated from Quang Ninh District to the Hung Doong area ("Hung" means valley) seeking refuge after a major flood impacted their village. Initially home to just five individuals, Ban Doong has grown to include 12 households with 52 residents as of 2022, while still maintaining the traditional features of the Bru-Van Kieu culture.

The journey to explore En Cave includes traveling through Ban Doong, situated in the core zone of Phong Nha-Ke Bang National Park. After departing from the Oxalis Phong Nha office, visitors begin their trek through the forest, descending a long slope to follow a branch of the Rao Thuong River, leading to one of the settlements within the park. To reach En Cave, visitors need to engage in physically demanding activities such as trekking, wading through streams, and climbing rocks.