The gigantic fresh water Lake Toba in North Sumatera is Southeast Asia's largest lake and the highest lake in the world. It covers an area of 1,700 squares kilometres and so far has defied effords to measure its depth, although it is known to be deeper than 460 metres.

It occupies the caldera of a massive volcano which exploded some 1000,000 years ago in the most powerful volcanic erruption ever known.

The island of Samosir , in the centre of the lake and the lake's eastern shore or the main tourist centre today are all that remain of the volcano's shattered cone. These cated amidst beautiful mountain scenery.

Parapat a prime tourist town, occupies a small rocky peninsula jutting into the lake. It has recently expanded over a ridge into the adjacent village of Ajibata , the ferry harbour to Samosir island. Parapat has a resort since before World War II. It has boomed in recent years with the opening of many new hotels. Good water skiing, speed boat trips, or power boating, paddle craft, tennis and golf are all available. Shops sell an array of Batak textiles, wood carving, ceramic and other goods mixed with the occasional genuine antiques. 

Samosir island, the huge, and "island of the dead" in the middle of Lake Toba, is a stark remnant of a second powerful explosion that rocked this volcanic cauldron some 30,000 years ago. In fact, was originally a peninsula only became an island 1906 after the Dutch dug canal through the narrow.

200-metres isthmus connecting Samosir island to the mainland at Pangururan. From Pangururan, a small town and administrative centre on the island western side, a road link to the mainland link climbs a steep escarpment which affords dramatic views from Tele, at height of 1,800 metres. It also offers a splendid panorama of the lake with Samosir Island spread out down below. Samosir island is accessible by ferry from the resort town of Parapat, a journey of under an hour, and less frequently by ferries from Haranggaol and Tigaras on the Simalungun Shore to the north. 

The two main ferry landing points on Samosir are Tomok a traditional village with beautiful houses astone tombs and houses, and Tuktuk , where the island have many hotels and restaurants. At Tomok, famous for years now as the "gateway to Samosir", the visitors is greeted by rows of stalls selling a bewildering array of Batak handicraft traditional Ulos cloth,carvings, Batak calendars and traditional Batak musical instrument. In Tomok Village is found the ancent royal stone tomb of the Sidabutar clan dynasty. Bodies were burried in the stone sarcophaguses under a large Banyan tree.  Four kilometres north of the village of Tuktuk along the narrow, paved road is Ambarita , an attractive village with ancient stone walls that were once topped with a thick Pagar or fence of thorny bamboo. Inside are stone seats and modern statuary the work of the Siallagan clan some 40 years ago.

The annual Danau Toba festival has been held since 1979 as a major event in North Sumatera and nowdays become one of the national core events througthout Indonesia beside the International Surfing Contest which held every year in Lagundri bay, Nias Island. The rich colour and diversity of North Sumatera cultures are displayed during this festival including the Toba Batak culture, as the hosts of this festival, their culture and traditions are in the forefront of the many performance.

The "Mangalahat Horbo" ritual ceremony, traditional 11 solu bolon or long canoe rowing competition, jet powered boat racing and a triathlon contest. Are among the many attractions of this festival. The annual Danau Toba festival which is held from June to July, has become one of the biggest tourist event in North Sumatera and South East Asian countries (Asean). The main route to Lake toba from Medan passed through Tebing Tinggi and Pematang Siantar the Simalungun Batak areas. However, there is a the scenic back road accross the Karo plateau from Berastagi that skirt the northeastern edge of Lake Toba caldera. This is alonger but far more visually exiting route with many interesting stops a long the way.

About 20 kilometres from Medan and traffic is soon left behind as you begin the climb into the forested foothills of the Bukit Barisan (mountin range). Sharp turns provide panoramic views back across the verdant plains to the city. Enroute to Berastagi, the Sibolangit Botanical garden lies on an escarpment overlooking Sembahe river and the lowlands. Berastagi is dominated immediately to the north by smoking Mountain Sibayak ehile further to the west is higher mountain Sinabung (2,451 metres).

Located on the northern outskirts of Berastagi, the village of Peceren has a number of traditional Karo Batak houses interspersed with more modern ones. Lingga village is located 16 kilometres southwest of the town near the source of Lau Garut an altitude of 1,200 metres. 

Further to the south past Kabanjahe (Ginger Garden) the district capital, the road touches the nothern rim of Toba basin at Merek, there's a side road from here that winds down to the lake shore past a spectacular waterfall known as Sipiso-piso (like a knife), which shoots out of a cave at the edge of the plateau and plunges 120 metres straight down to a small, gushing stream below. A gazebo provides a panoramic view the village of Tongging .