Thach An

Thạch An is a mountainous rural district in southern Cao Bằng Province, positioned along National Route 4A between Cao Bằng City and Lạng Sơn Province. The district capital is Đông Khê, a small settlement surrounded by limestone hills. Thạch An is best known as the central theater of the 1950 Battle of Đông Khê, which launched the decisive Border Campaign during the First Indochina War and ended French control of Route Coloniale 4 (RC4).

The district forms part of the Non Nước Cao Bằng UNESCO Global Geopark, specifically featuring on the southern "A Time of Fire and Flowers" heritage route. Beyond its wartime battlegrounds and memorial sites, Thạch An is northern Vietnam's leading producer of thạch đen (black grass jelly), cultivated across agricultural valleys in communes like Lê Lai and Đức Thông.

The geography consists of steep karst peaks, dense mountain woodland, and narrow valleys drained by small tributaries of the Bằng and Kỳ Cùng river systems. The climate is subtropical and highland-influenced, with hot, rainy summers from May to September and cool, dry winters from November to March, when nighttime temperatures frequently drop below 10°C.

By Air

No air service exists in Thạch An or Cao Bằng Province. The nearest major airport is Noi Bai International Airport (HAN) in Hanoi, roughly 240 km southwest. HAN receives domestic and international flights from carriers including Vietnam Airlines, Vietjet Air, and Bamboo Airways (approx. 1 hour 20 minutes flight from Da Nang, 2 hours from Ho Chi Minh City). From Hanoi, travelers continue overland to Đông Khê by bus, limousine van, or private car.

By Bus

Direct sleeper and seating buses connect Hanoi, Lạng Sơn, and Cao Bằng City to Đông Khê town center along National Route 4A:

• From Hanoi (Mỹ Đình, Giáp Bát, and Nước Ngầm stations): Long-distance coach operators including Khánh Hoàn, Thanh Ly, and Hiệp Bình run direct buses to Cao Bằng via Đông Khê. Trips depart 4–6 times daily, take 5 to 6 hours, and cost between 200,000 and 300,000 VND ($8–$12 USD) one way.
• From Cao Bằng City: Local public buses (Route 01) and private minibuses depart Cao Bằng Central Bus Station every 30 to 60 minutes between 06:00 and 17:00. The 45 km trip along National Route 4A takes about 1 hour and costs 35,000 to 50,000 VND ($1.40–$2.00 USD).
• From Lạng Sơn / Thất Khê: Passenger vans run north on QL4A through Thất Khê (Tràng Định) to Đông Khê hourly throughout the day (approx. 75 km, 2 hours, 60,000–80,000 VND / $2.40–$3.20 USD).

By Train

No train service exists in Thạch An. The nearest railway station is Đồng Đăng Railway Station (DD) in Lạng Sơn Province, approximately 75 km south, on the Hanoi–Đồng Đăng line operated by Vietnam Railways (Đường sắt Việt Nam). From Đồng Đăng, onward travel to Thạch An requires a taxi or a local bus heading north on National Route 4A.

By Car

• From Cao Bằng City: Follow National Route 4A (QL4A) directly south for 45 km. The drive takes roughly 1 to 1.5 hours over paved, winding roads.

• From Hanoi: Drive north via the Hà Nội–Bắc Giang–Lạng Sơn Expressway (CT01 / QL1A) to Lạng Sơn City (150 km, ~2 hours), then head northwest on National Route 4A through Thất Khê to Đông Khê (85 km, ~2.5 hours). Total driving distance is around 235 km (4.5 to 5 hours).

• From Quảng Hòa / Tà Lùng Border Gate: Follow Provincial Road DT208 southwest across the mountain passes for 38 km to connect with Đông Khê (approx. 1 hour).

• Motorbike: Renting a motorbike is the most effective method to reach outlying communes and geopark geological sites. Rentals are available at guesthouses in Đông Khê or in Cao Bằng City for 150,000 to 200,000 VND ($6–$8 USD) per day.

• Motorbike Taxi (Xe Ôm): Local drivers wait near the Đông Khê central market and main bus stops. Fares within town run 20,000 to 30,000 VND ($0.80–$1.20 USD); trips to Báo Đông Mountain or outlying communes cost 70,000 to 120,000 VND ($2.80–$4.80 USD). Agree on the price before riding.

• Ride-Hailing Apps: Grab and Gojek do not operate in Thạch An District.

• Walking: Đông Khê town center is small; the local market, eateries, and historic fort monuments can all be reached on foot from central guesthouses.

• Đông Khê Victory Historical Site & Fort (Di tích Chiến thắng Đông Khê / Đồn Đông Khê) — Situated in Đông Khê town, this historic complex preserves the reinforced concrete bunkers, trench networks, and artillery emplacements of the French colonial garrison overrun in September 1950. A central monument commemorates hero La Văn Cầu. Free entry.

• Báo Đông Mountain Command Post (Đài quan sát Bác Hồ trên núi Báo Đông) — Located in Đức Long Commune, 15 km east of Đông Khê. An 845-step stone stairway leads through mountain woodland to the rocky peak where President Ho Chi Minh personally observed and commanded the 1950 Battle of Đông Khê. The summit features a life-size stone monument and panoramic valley views. Free entry.

• Khau Khoang Pass Pillow Basalt Site (Đèo Khau Khoang) — An official geological heritage stop on the Non Nước Cao Bằng UNESCO Global Geopark in Thái Cường Commune. Rock outcrops along the road show well-preserved pillow basalts created by underwater volcanic eruptions on an ancient ocean floor 260 million years ago. Free entry.

• Ngườm Pục Cave (Hang Ngườm Pục) — Located in Lê Lợi Commune near the border with Lạng Sơn Province. A deep karst cavern descending roughly 100 meters into limestone formations, featuring multi-tiered chambers with untouched stalagmites and natural stone columns. Free access; hire a local guide for navigation.

• Khau Luông Pass (Đèo Khau Luông) — A mountain pass on National Route 4A near the southern boundary with Lạng Sơn Province, providing expansive views across karst cliffs along the former French colonial supply line. Free roadside access.

• Thạch Đen Cultivation Valleys (Lê Lai & Đức Thông Communes) — Farmlands and processing workshops dedicated to growing black grass jelly (Platostoma palustre), the district's registered agricultural specialty. Free to visit.

• Drive the Geopark Route "A Time of Fire and Flowers": Ride or drive the designated UNESCO geopark trail connecting Cao Bằng City, Thạch An, and Quảng Hòa along QL4A and DT208, stopping at war relics, ancient volcanic pillow basalts, and fossil points.

• Climb Báo Đông Mountain: Tackle the 845 stone steps up Báo Đông Peak in Đức Long Commune to reach the summit observation post and vantage point over the historical battlefield.

• Sample Fresh Black Grass Jelly: Visit the morning market in Đông Khê to try freshly processed black grass jelly served chilled with light sugar syrup.

• Ride the Historic Route 4 (RC4): Motorbike the scenic, winding stretches of National Route 4A between Thất Khê and Đông Khê, passing karst canyons, hill passes, and war memorial markers.

• Nhà hàng Đông Khê (Chang Khuyên Quarter, Đông Khê Town) — A spacious eatery serving local mountain specialties such as hill chicken (gà đồi), stir-fried beef with wild greens, braised pork knuckle, and freshwater fish. Price tier: Mid-range (80,000–180,000 VND / $3.20–$7.20 USD per dish).
• Nhà hàng Tân Dân (Chợ Mới area, Đông Khê Town) — Popular dining spot near the market specializing in chicken hot pots (lẩu gà), mixed hot pots, roast pork, and family-style rice platters. Price tier: Budget to mid-range (60,000–150,000 VND / $2.40–$6.00 USD per person).
• Nhà hàng Xuân Quyên (Tổ dân phố 1, Đông Khê Town) — Family-run roadside eatery preparing stir-fried mountain pork, braised pork with black canarium (thịt kho trám), and seasonal greens. Price tier: Budget (50,000–100,000 VND / $2.00–$4.00 USD per dish).
• Quán Bánh Cuốn & Phở Đông Khê (National Route 4A, Đông Khê Town center) — Morning stall serving hot Cao Bằng-style steamed rice rolls (bánh cuốn) served with a bowl of rich bone broth, herbs, and minced pork, as well as roast duck noodle soup (phở vịt quay). Price tier: Budget (30,000–45,000 VND / $1.20–$1.80 USD per bowl).

• Nhà nghỉ Thiên Việt (National Route 4A, Đông Khê Town) — Clean budget guesthouse offering private rooms with air conditioning, en-suite bathrooms, hot water showers, and Wi-Fi. Budget: 200,000–250,000 VND ($8–$10 USD) per night.
• Khách sạn Thạch An (72 National Route 4A, Đông Khê Town) — The district center's primary hotel with 18 furnished rooms, 24-hour desk, secure parking, and television. Budget to mid-range: 250,000–400,000 VND ($10–$16 USD) per night.
• Nhà nghỉ Bảo Ngân (National Route 4A, Đông Khê Town) — Convenient roadside lodging suited for motorbikers and bus travelers transiting along QL4A. Budget: 180,000–220,000 VND ($7–$9 USD) per night.
• Nhà nghỉ Giang Sơn (Đức Long Commune, near Báo Đông Mountain) — Basic rural guesthouse providing simple rooms close to the Báo Đông historical site. Budget: 150,000–200,000 VND ($6–$8 USD) per night.
• Upscale / Luxury: No upscale or luxury hotels exist in Thạch An District. Travelers seeking luxury lodging should stay in Cao Bằng City (45 km north; e.g., Mường Thanh Luxury Cao Bằng or Max Boutique Hotel, $35–$70 USD per night).

• Thạch Đen Thạch An (Black Grass Jelly): The district's signature OCOP-certified specialty. Buy fresh blocks, ready-to-eat cups, or packaged dried herb bundles (Platostoma palustre) produced by local processing facilities in Lê Lai and Đông Khê (30,000–60,000 VND / $1.20–$2.40 USD per box).
• Trám Đen (Black Canarium Fruit): A wild mountain fruit harvested in autumn, preserved in salt or fermented for cooking with braised pork and sticky rice.
• Lạp Sườn Gác Bếp (Smoked Mountain Sausage): Pork sausage seasoned with local spices and ginger, smoked slowly over kitchen wood fires by Nùng and Tày villagers.

• Cao Bằng City — 45 km north via National Route 4A (1–1.5 hours drive). The provincial capital provides extensive hotels, lively night markets, and access to the northern geopark circuits.
• Quảng Hòa District & Tà Lùng Border Gate — 38 km northeast via Provincial Road DT208 (1 hour drive). Known for traditional blacksmithing villages at Phúc Sen, sugar cane fields, and the international border post with China.
• Lạng Sơn City & Thất Khê — 75 km south via National Route 4A (2 hours drive). A major border city featuring Tam Thanh Cave, bustling trade markets, and the Hữu Nghị International Border Gate.
• Bản Giốc Waterfall & Ngườm Ngao Cave (Trùng Khánh District) — 135 km northeast via Cao Bằng City and QL3/DT206 (3.5–4 hours drive). Vietnam's largest waterfall on the Chinese border and an extensive multi-kilometer karst cave system.