Arrive in Medan, the capital of North Sumatra and Indonesia's third largest city. A vibrant trading hub, the city has been shaped by centuries of migration and commerce, creating a fascinating mix of Malay, Batak, Chinese, Indian and Dutch influences. This rich cultural heritage is reflected in Medan's architecture and, perhaps most famously, its diverse food scene, where street food stalls sit alongside traditional coffee shops and local restaurants. For those arriving on time, our tour leader plans to meet you in the hotel reception at 6pm for a welcome meeting and for those that wish, there is the chance to meet your fellow travellers over dinner at the hotel's restaurant. If you'd like an airport transfer today, you'll need to arrive into Medan Kualanamu International Airport (KNO), a one-hour hour drive from our hotel. Should you miss the welcome meeting, your tour leader will inform you of any essential information over breakfast on day two. If you'd like to beat the jetlag by adding an extra night or two to the beginning of your tour, contact us to book accommodation.

First thing in the morning we discover two of Medan's most significant landmarks. We begin at Maimun Palace, the former royal residence of the Sultanate of Deli, whose striking architecture blends Malay, Islamic and European influences. We then visit the magnificent Great Mosque (Masjid Raya Al Mashun), one of Indonesia's finest mosques. Subject to prayer times, we hope to step inside to admire its ornate interior and learn about its importance to the local community. After our visit, we leave the city behind and drive for approximately three hours to Bukit Lawang, our gateway to Gunung Leuser National Park. Along the way, we'll pass villages, rice paddies and extensive oil palm plantations. Palm oil remains an important part of Indonesia's economy despite its well-known environmental challenges, and our tour leader will provide balanced local insight into this complex issue. On arrival, we'll check-in into our accommodation which is located on the edge of the national park. Rooms are simple but comfortable, with en suite facilities and fans. As this is a remote rainforest location, air conditioning is not available and hot water can occasionally be limited. After an early dinner, we'll meet our local guide and head into Gunung Leuser National Park for a guided night walk. Following a different trail from tomorrow's trek, we explore beneath the rainforest canopy at a relaxed pace, discovering how the forest transforms after dark. As daylight fades, our focus shifts to the park's nocturnal wildlife, and with luck we may encounter insects, frogs, geckos, civets, sleeping birds and, occasionally, the elusive slow loris, while listening to the sounds of the rainforest at night. This walk offers a fascinating introduction to the diversity of life within Gunung Leuser National Park ahead of tomorrow's longer rainforest trek. The walk covers up to 2 kilometres/1.2 miles on mainly flat forest trails and takes around three to four hours, allowing plenty of time for wildlife observation. Our overall driving time today is around three hours.

This morning we venture once more into the rainforest of Gunung Leuser National Park, accompanied by our tour leader and an experienced local wildlife guide. We follow narrow jungle trails beneath the dense forest canopy in search of one of Sumatra's most iconic residents - the critically endangered Sumatran orangutan. Bukit Lawang was once home to an orangutan rehabilitation centre, but today the animals here live freely within the national park. Although sightings can never be guaranteed, this remains one of the best places in the world to observe wild orangutans behaving naturally in their forest habitat. The rainforest supports an extraordinary diversity of wildlife and, with luck, we may also encounter endemic birds and a variety of reptiles, while the forest itself teems with butterflies, insects and tropical birdlife. Gunung Leuser National Park also provides a vital refuge for elusive Sumatran tigers, elephants and rhinoceroses, although these are very rarely seen. Today's walk covers approximately 5 kilometres/3 miles and takes up to four hours, including time spent observing wildlife. The trails are uneven and can be muddy or slippery, with exposed tree roots, with some short but very steep sections and around 225 metres/738 feet of ascent and descent. While the distance is relatively modest, the tropical heat and humidity make the walk considerably more demanding than it may appear, so a good level of fitness and confidence walking on uneven terrain are essential. Later this afternoon we visit Project Wings, an inspiring community-led recycling project working to tackle plastic pollution while supporting rainforest conservation and local livelihoods. During our visit we'll learn how discarded PET bottles are transformed into eco-bricks by filling them with cleaned plastic waste, creating durable building blocks used throughout the village. We'll enjoy a guided tour of the project, watch an eco-brick making demonstration and visit the e-gallery to learn more about the organisation's environmental work and the positive impact it is having on local communities. We round off the visit with dinner at the project before returning to our accommodation.

Leaving the rainforest behind, today's full day scenic drive takes us into the cool highlands of North Sumatra. As we climb through the mountains, dense tropical forest gradually gives way to fertile farmland, pine trees and small villages surrounded by fruit and vegetable plantations. We'll make several stops along the route, including opportunities to sample seasonal tropical fruits from roadside stalls before arriving in Berastagi, a bustling market town sitting at around 1,300 metres/4,265 feet above sea level. The cooler climate provides a welcome contrast to the humidity of the rainforest. Late this afternoon we visit Berastagi's colourful fruit and vegetable market, where local farmers sell everything from sweet passionfruit and avocados to fragrant spices and seasonal produce grown on the surrounding volcanic soils. We recommend getting an early night tonight as we'll be heading out early to catch the sunrise. Our overall driving time today will be around seven hours.

A very early start rewards us with cooler temperatures as we set out to climb Mount Sibayak (2,100 metres/6,890 feet) with an experienced local mountain guide. Although only relatively short in length, today's walk is one of the most physically demanding of the trip. After leaving our vehicles, we climb approximately 400 metres/1,315 feet on rocky volcanic paths, uneven steps and loose gravel before reaching the steaming crater. Sulphur vents hiss and, on a clear morning, the summit offers superb views across the surrounding volcanic landscape. The ascent usually takes around two hours at a steady pace. The route can be slippery after rain, and the combination of steep gradients, uneven ground and volcanic terrain requires good balance and fitness. Using walking poles may be beneficial for additional support. After descending, we return to the hotel for breakfast and a chance to freshen up before continuing our journey towards the vast caldera of Lake Toba. Along the way we stop at Dokan, a traditional Karo Batak village where distinctive wooden houses provide an insight into local life and customs, before visiting the spectacular Sipiso-Piso Waterfall, which plunges over 100 metres into the ancient volcanic crater below. Continuing to Parapat, we board the ferry across Lake Toba to Samosir Island, our base for the next two nights. Our total drive today is around four hours, followed by a half-hour public ferry.

Today we explore Samosir Island, situated in the heart of Lake Toba, the world's largest volcanic lake. This water-filled giant caldera was formed following one of the largest volcanic eruptions in Earth's history around 74,000 years ago. The lake dominates the surrounding landscape and remains the cultural heartland of the Batak people. Travelling by boat and road, we visit several traditional Batak villages including Tomok, Ambarita and Simanindo. Along the way we learn about Batak history, architecture and customs, visiting ancient stone chairs once used for village meetings and justice, elaborately carved ancestral tombs and beautifully preserved traditional houses with their distinctive soaring roofs. At Simanindo we gain further insight into Batak culture hopefully through displays of traditional music and dance, depending on local schedules. Returning to our lakeside hotel during the afternoon, the remainder of the day is free to relax, enjoy the peaceful surroundings or perhaps take a refreshing swim in the lake.

After breakfast we leave Samosir Island by the same public ferry before beginning the four-to-five-hour drive back to Medan, passing fertile farmland, plantations and mountain scenery along the way. On arrival in the city we explore the historic Kesawan district on foot. Once the commercial heart of colonial Medan, the area is home to beautifully preserved heritage buildings, Chinese shophouses and bustling local businesses that reflect the city's multicultural past. The remainder of the afternoon is free for last-minute shopping, relaxing at the hotel or sampling some of Medan's renowned local cuisine before our final evening together.

The trip ends after breakfast at our hotel in Medan. There are no activities planned today, so you\ re free to depart from Sumatra at any time. If your flight is departing later in the day, luggage storage facilities are available at our hotel. If you\ d like an airport transfer today, you'll need to depart from Medan Kualanamu International Airport (KNO), which is just under a one-hour drive from the hotel.