Introduction to Sandiaoling Tunnel
Taiwan’s Hidden Trail Through History and Nature
If you’re searching for a unique blend of history, adventure, and scenic beauty in northern Taiwan, look no further than the Sandiaoling Tunnel (三貂嶺隧道). Once a forgotten piece of railway history, this former train tunnel has been beautifully restored and transformed into a pedestrian and cycling trail, offering travelers a peaceful escape through lush greenery, mountain views, and echoes of Taiwan’s industrial past.
▼ Mudan Station
A Scenic Blend of Nature and Heritage
Hidden in the quiet hills of Ruifang District, the Sandiaoling Tunnel Trail offers an extraordinary experience where natural beauty and industrial history converge. The trail follows part of the historic Yilan Railway Line, a section once used to connect small mountain towns.
After decades of abandonment, this stretch has been transformed into a walking and cycling path that honors its legacy while inviting modern-day travelers to experience a peaceful, immersive escape into Taiwan’s lush backcountry.
Surrounded by thick forests, bamboo groves, and mountain mist, the atmosphere is quiet and calming — a stark contrast to the noise of city life. It’s not just a walk through a tunnel; it’s a journey into Taiwan’s forgotten railway past.
Every step along the trail offers scenic vistas, bird sounds, and the occasional train running on the active line nearby, reminding you that even in quiet places, history still moves forward.
▼ Continue walking or riding a Youbike in this direction
A Journey Through Forgotten Tracks
The heart of the trail lies in its tunnels — most notably the beautifully restored Tunnel No. 3, the longest and most iconic of the series. Inside, original railway tracks and iron ties have been left in place, offering an authentic look at early 20th-century rail engineering.
Subtle ambient lighting helps guide you, while the sound of your footsteps echoing off the stone walls creates a surreal, almost cinematic experience. The cool, damp air inside gives the tunnel a sense of mystery, transporting you to a time when trains were the only way through the mountains.
Throughout the route, you’ll find historic elements left untouched — such as weathered signal posts, rusted switch levers, and moss-covered stonework that give the area a timeless feel.
Informational plaques explain the history of the line, offering insight into the role this railway once played in Taiwan’s development. For those interested in heritage travel or photography, this trail provides endless inspiration.
A Trail for All Ages
One of the most appealing aspects of the Sandiaoling Tunnel Trail is its accessibility. Unlike many of Taiwan’s more challenging mountain hikes, this trail is relatively flat, paved, and easy to navigate, making it ideal for families, casual walkers, and even seniors.
At around 3.19 kilometers one way, it’s long enough to feel like a mini adventure, but short enough to enjoy at a leisurely pace. There are no steep climbs or tricky terrain, so even young children or first-time visitors can explore comfortably.
In addition to walking, the trail is also bike-friendly, and YouBike stations near nearby Mudan Train Station makes it convenient to rent a bicycle for the trip. The path includes bike racks and shaded rest stops along the way, offering breaks for those who want to slow down and enjoy the view. Whether you’re on foot or two wheels, the Sandiaoling Tunnel Trail offers an easy yet enriching outdoor experience perfect for all ages.
▼ Continue walking or riding a Youbike along the railway in this direction.
By Reservation Only
To maintain the delicate environment and ensure a high-quality experience, access to the Sandiaoling Tunnel is limited to visitors with online reservations. You’ll need to book a time slot through the official website before your visit, and present the QR code upon arrival.
Each time slot allows up to 160 people, which helps reduce congestion and lets visitors enjoy the trail in a calm, respectful setting. This approach not only protects the environment, but also enhances your overall experience.
The system has proven effective, particularly during weekends and peak seasons when interest is high. It’s recommended to reserve at least 7 to 14 days in advance, especially if you plan to visit during holidays or school breaks.
This added step may seem small, but it ensures that your walk through the tunnel remains tranquil and uncrowded — just as it should be.
More Than Just a Tunnel
While the tunnel itself is the main highlight, Sandiaoling is surrounded by some of the most underrated attractions in the Pingxi region.
From Sandiaoling Station, you can embark on a separate waterfall hiking trail, which takes you past three stunning cascades — Hegu, Motian, and Pipa Waterfalls — all accessible via suspension bridges and forested trails. For nature lovers and photographers, this trail is a hidden treasure.
Nearby Houtong Cat Village offers a completely different vibe — quirky, charming, and full of cats lounging on rooftops, stairs, and cafes. If you still have time, continue along the Pingxi Line to Shifen Old Street and Shifen Waterfall, Taiwan’s broadest waterfall, or write your wishes on a sky lantern and release it from the nostalgic Shifen Old Street.
A trip to Sandiaoling is more than just a tunnel walk — it’s a doorway into some of Taiwan’s most scenic and culturally rich countryside.
What to See Along the Trail
The Sandiaoling Tunnel is 3.19 kilometers long and is the first tunnel in Taiwan to use reinforced concrete pavement. The old Sandiaoling Tunnel, which has been closed for 37 years, will be transformed into a natural ecology using an environmentally friendly construction method, giving you the opportunity to see upside-down bats when you look up in the tunnel.
The Sandiaoling Tunnel Trail is not just about walking through an old railway tunnel — it’s a scenic and historical journey. As you make your way along the 3.19-kilometer trail, you’ll pass through several restored railway tunnels, including the iconic Sandiaoling Tunnel No. 3, which is the longest and most photogenic.
Inside the tunnel, original steel tracks, moss-covered stone walls, and soft lighting give it a mysterious yet inviting charm. Outside the tunnels, the trail offers lush mountain views, native flora, and peaceful surroundings perfect for nature lovers.
You’ll also spot historical railway signs, an old signal light system, and interpretive panels that explain the tunnel’s past as part of the Yilan Line. The route is flat and well-paved, making it ideal for walking, biking, or even a casual stroll with kids.
▼ Bring your QR code confirmation for check-in at the entrance. Starting from the rest stop, the road is paved with steel bars. Walk about 50 meters to reach the entrance of Sandiaoling Tunnel.
Key Highlights
Sandiaoling Tunnel – The longest, most scenic tunnel with soft lighting and original tracks.
Restored railway features – Vintage signal lights, track signs, and interpretive history panels.
Lush mountain scenery – Peaceful views, greenery, and birdsong throughout the route.
Flat, safe path – Suitable for walking, cycling, and family-friendly exploration.
Things to Do in Sandiaoling Tunnel
Whether you’re a nature lover, history buff, or casual traveler, the Sandiaoling Tunnel Trail offers a rewarding mix of outdoor fun and cultural discovery. Here are the top things to do when visiting this unique spot in New Taipei City:
Safety Tips
● Sandiaoling Tunnel is a reservation system. Please make a reservation on the official website in advance. (here)
● Reservations are made in stages on holidays, and there is a total number of people on weekdays.
● There is ecological conservation in the tunnel, please do not make noise, capture or use flash.
● The lighting is dim, so watch your step and stay quiet to respect others (bats).
● No pets or large luggage allowed to protect the environment.
● The tunnel floor is made of steel bars — wear non-slip shoes.
● There is occasional dripping water in the tunnel, it is recommended to wear a hat or helmet.
▼ The tunnel walls look like stalactites and colorful rock walls
Walk Through the Historic Tunnel
The star attraction of the Sandiaoling Tunnel, the longest and most atmospheric of the preserved railway tunnels. As you step inside, you’re immediately transported to a different time.
The path remains lined with original railway tracks, and the damp, mossy walls create a cool and quiet environment. Subtle LED lighting guides your way, making the tunnel feel safe yet mysterious.
This tunnel was part of the former Yilan Line and retains much of its early 20th-century character. Walking through it is not just scenic, but emotional — a quiet moment where history, nature, and solitude meet.
It’s a favorite spot for photographers, urban explorers, and anyone looking for a unique walk off the beaten path.
Key Point:
Walk through a historic, preserved railway tunnel with original tracks, mossy walls, and cinematic lighting.
The tunnel is 3.19 kilometers long and takes about 50 minutes to walk one way, or about 100 minutes to walk back and forth.
Cycle the Tunnel Trail
For those who prefer to cover more ground, cycling the Sandiaoling Tunnel Trail is an excellent option.
You can rent a YouBike 2.0 at nearby Houtong or Mudan Station and ride directly to the trail entrance. The path is mostly flat and well-paved, making it perfect for a casual, relaxing ride suitable for all fitness levels.
Along the way, you’ll pass scenic mountain views, old railway structures, and quiet forests. The tunnel itself is bike-friendly, and bike racks are available at the entrances.
It’s a great way to combine outdoor activity with sightseeing, especially for families or couples on a day trip.
Key Point:
Rent a bike nearby and enjoy an easy, scenic ride through the railway trail and tunnel.
It may be difficult to rent a YouBike during peak hours on weekends, so it is recommended to go on weekdays.
▼ The tunnel floor is made of steel bars with gaps on the surface.
Take Stunning Photos
Sandiaoling Tunnel is a photographer’s dream. The contrast between natural light at the entrances and the tunnel’s dim, misty interior creates dramatic shots.
The old tracks, rustic textures, and echoing hallway offer a timeless, moody atmosphere — ideal for portraits, travel photos, or cinematic-style scenes.
Outside the tunnel, the surrounding forest and trail are equally photogenic. You’ll find bamboo groves, overgrown signal poles, and abandoned tracks, all perfect for storytelling visuals.
Whether you’re using a DSLR or your phone, there are plenty of Instagram-worthy spots.
Key Point:
Capture unique photos of railway ruins, tunnel interiors, and lush scenery.
▼ At the end of the tunnel, you can also take a photo of your reflection in the water.
Discover Railway Artifacts
The trail doubles as an open-air museum of Taiwan’s early railway history. Scattered along the route are authentic signal lights, control levers, track switches, and old signage that were once part of the operational train line.
These relics are preserved and marked with informational plaques in Chinese, giving context to their use and history.
For railway fans or curious travelers, these small details add incredible value to the experience. They provide insight into Taiwan’s transportation past and the people who once operated trains in this rugged terrain.
It’s an ideal blend of nature walk and educational outing.
Key Point:
Discover historic railway equipment and learn about the tunnel’s past through preserved relics.
Bats in Sandiaoling Tunnel: Nature Coexisting with History
As you walk through Sandiaoling Tunnel, especially in the cooler, darker sections, you may notice small bats resting quietly on the tunnel ceiling. These are typically native insect-eating bats that find the damp, shaded environment ideal for roosting during the day.
▼ Flash photography or riding Youike is not permitted in bat-marked areas.
There’s no need to be alarmed — the bats are harmless, shy, and do not pose a danger to visitors as long as they’re not disturbed. In fact, they’re a great sign that the tunnel is ecologically healthy.
Avoid using bright flashlights or making loud noises, and you’ll likely pass through unnoticed by them. Spotting some bats simply adds to the tunnel’s mysterious, natural charm.
At present, security personnel are stationed at both ends of the bat habitat in the tunnel. Visitors are reminded at any time to stop riding in front of the sign when riding through the bat habitat, use a towed bicycle to pass, and keep quiet.
▼ There are bat warning signs on both sides of the tunnel.
When visiting the Sandiaoling Ecological Tunnel, please obey the instructions of the on-site management personnel and security personnel to ensure the maintenance of the ecological environment in the tunnel.
Key Points:
Bats live in the tunnel, especially in darker and cooler sections.
They are harmless and an important part of the ecosystem.
Visitors should avoid disturbing them (no loud noises or bright flashes).
Enjoy Nature and Wildlife
One of the most rewarding parts of the Sandiaoling experience is the natural setting. The trail winds through forests, creeks, bamboo groves, and mountain slopes — making it feel far removed from urban life. You’ll hear birds singing, spot butterflies fluttering by, and sometimes see wildflowers growing along the path.
If you enjoy quiet walks in nature, this trail delivers serenity in abundance. It’s ideal for birdwatchers and nature photographers, or anyone who simply wants to slow down and breathe in fresh mountain air. The environment changes with the seasons, offering new sights year-round.
Key Point:
Immerse yourself in forested surroundings filled with birds, butterflies, and seasonal beauty.
Connect to Other Trails and Spots
Sandiaoling Tunnel is just the beginning — the area connects to several nearby attractions, making it easy to turn a short visit into a full-day trip. From Sandiaoling Station, you can start the famous Sandiaoling Waterfall Trail, which takes you to three stunning waterfalls via forest paths and suspension bridges.
You can also hop back on the Pingxi Railway Line to explore Houtong Cat Village, Shifen Waterfall, and Shifen Old Street, all within a few stations.
Each stop offers something unique — from cats and cafes to waterfalls and sky lanterns. It’s an ideal way to explore Taiwan’s nostalgic countryside at a slow, rewarding pace.
Key Point:
Connect your visit with nearby waterfalls, cat villages, or sky lanterns for a full-day Pingxi adventure.
Nearby Attractions
Sandiaoling is part of the scenic Pingxi railway region, meaning you can easily combine your tunnel walk with other nearby sights:
Houtong Cat Village – Just one station away, this feline-themed village is famous for its free-roaming cats, cat cafes, and quirky shops. Great for kids and cat lovers.
Shifen Old Street – Known for its sky lanterns and old-town vibes. Release a lantern, try local snacks, and enjoy a nostalgic slice of Taiwanese culture.
Shifen Waterfall – A short train ride away, this wide, dramatic waterfall is often called “Taiwan’s Niagara Falls.” There’s also a suspension bridge and viewing platform.
Sandiaoling Waterfall Trail – A beautiful hike that begins near Sandiaoling Station. It features three major waterfalls, suspension bridges, and dense forest. A perfect half-day add-on for hikers.
Opening Hours
Opening Hours: 08:3–16:30 (last entry at 16:00)
Closed Mondays
Price
Cost: Free Entrance
The Sandiaoling Ecological Tunnel implements an online reservation system. You can enter the tunnel only after completing the formalities. You must apply for admission online before your visit (here)
No fees are charged during the operation period. Please do not purchase tickets through unknown channels.
▼ Using steel bars to mark distances
Best Times to Visit
The best time to visit the Sandiaoling Tunnel Trail is during cooler, drier months — typically from October to April. During this period, temperatures are comfortable for outdoor activity, and the surrounding forest is rich in color, especially in late autumn.
Avoid visiting during peak summer (June to August), when high humidity and heat can make the trail less pleasant. Weekdays are best if you prefer a quieter, more relaxing experience, while weekends and holidays may bring larger crowds due to the tunnel’s rising popularity.
No matter when you go, be sure to book your time slot in advance, especially if you’re visiting on a weekend.
Key Tips:
Best season: October to April (cooler, more comfortable weather).
Avoid: Summer months (hot and humid), especially midday.
Best days: Weekdays are quieter; weekends require early reservations.
Reserve ahead: Online booking required — especially during holidays.
With a mix of railway nostalgia, natural beauty, and eco-friendly exploration, the Sandiaoling Tunnel is a hidden gem perfect for a day trip from Taipei. Just remember to plan ahead, book your slot, and enjoy the journey at your own pace.
▼ There are only a few shops left on Mudan Old Street, but there are still a few snack stalls on the road to the left of the train station.
How to Get to Sandiaoling Tunnel
The Sandiaoling Tunnel is located in Ruifang District, New Taipei City, and is part of a beautifully restored section of a historic railway line.
It’s now a popular walking and biking path through scenic mountain landscapes. To preserve the environment and visitor experience, entry is limited and requires an online reservation in advance.
By Train (Most Recommended)
Start from Taipei Main Station and take a Taiwan Railways (TRA) train.
You can get off at either:
Mudan Station: Around 0.9 km from the tunnel (recommended: Walk or YouBike). It takes about 900 meters to walk from Mudan Station to the tunnel entrance, about 10-15 minutes.
Houtong Station: About 3 km from the tunnel entrance (a scenic walk or short bike ride).
Please do not take the train to Sandiaoling Station: there is no access to the tunnel from this station.
Both stations are connected to the trailhead by YouBike 2.0 stations, allowing you to easily rent a public bicycle for the short, scenic ride to the entrance.
Whether you walk or cycle, the approach to the tunnel offers a serene transition into nature. Along the way, you’ll pass bridges, streams, and forest paths that ease you into the slower rhythm of rural Taiwan — a welcome shift from the fast pace of the city.
By YouBike (Public Bike Sharing)
Both Houtong and Mudan stations offer YouBike 2.0 rental stations, allowing you to cycle to the tunnel entrance easily.
There are bike parking spots available near both tunnel entrances, making this a fun and flexible option.
Entry Reservation Required
To maintain visitor safety and protect the environment, all visitors must book a time slot online before entering the tunnel.
Visit the official reservation website. You must apply for admission online before your visit (here)
Select your preferred date and time (each slot has a limit of 160 people).
Book at least 2 weeks in advance, especially during weekends or holidays.
Bring your QR code confirmation for check-in at the entrance.