Mount Pangulubao, rather known locally as Bukit Manja, is situated by the east coast of Lake Toba, world's largest volcanic caldera and one of Sumatra's most visited destinations. It is well-known for the endemic pitcher plants and the various species of orchids it hosts on its slopes. With the contribution of some luck, one may also encounter some of the rare, stentorian Siamangs inhabiting it. It does receive few visitors, who will commonly only go as far as the viewpoint/camping-ground at 1760 amsl. Only at very rare occasions hikers will continue further up till the cement-pillar at 2150 amsl. Even there, however, it is not the actual highest point of the mountain. That lies another 2 km further into dense jungle and some 50 m higher after the pillar. As the people of the local community told me, no one has ever reached that point, as far as they're aware of. An expedition to that very top of the mountain would definitely be a very interesting one, but the ones who are to undertake it should allow themselves at least an extra full day and carry a sharp machete.
The closest transport-hub to the mountain is the town of Parapat at the shore of Lake Toba. It may be reached in about 4-5 hours from Medan, provincial capital of North Sumatra, or from any other city in Sumatra, the suited number of bus-changes and travel hours given. The trailhead is to be found at the "Taman Eden" gardens: a locally well-known, award-winning conservation project, 16 km south of Parapat. To get there from Parapat you can easily catch a mini-bus from the main road, passing from the outskirts of the town, for 10000 IDR. You can also find some sort of transport or another from the center of the town, but you will need to pay significantly more.
The mini-bus shall drop you off right in front of the entrance of Taman Eden. In order to get to the trailhead one needs to follow the main path leading through the gardens till the trail is signposted as "hiking trail" at a point to the right. From there on the trail is obvious for some time and there are a few signs leading along the way to "Bukit Manja". One of them does direct to the right off the obvious trail, which, if taken straight, leads after a short while to a deep and narrow gorge with a few waterfalls worth to be seen. Taking the right to "Bukit Manja", the trail is then far from obvious, discernible enough though to easily lead to the next sign, nailed on the trunk of a pine and directing straight, that's the last sign to be encountered. On the left of this sign there is a ditch starting, which might had been a trail at some time. If followed, zigzagging lavishly through the jungle and constantly pushing against ferns and shrubs, it will after 15-20 m lead to a rivulet. That's the only water source to be found. After this point one should carry ample quantity of water.
Back to the last sign, going straight you enter a pine-forest. There is nothing as a definite route I managed to detect. The forest is quite open making it possible to walk anywhere, thus a bit tricky to find the way through it. The best thing to do is to keep right by the side of the ravine and head steadily east until facing the steep slope of the mountain. Less than a 100 m from there, moving northwards along the foot of the slope, the trail may be seen ascending the steep slope in straight line. This part of the trip is an arduous one. The angle of the slope is nearly right at points, the ground is generally muddy and slippery and, in many parts, roots or branches to grasp are totally lacking, obliging you to fall on fours and creep up. Finally, after an hour or two of exertion you reach a small, flat glade signified with an Indonesian flag as the camping-ground at 1760 amsl.
That's how far people usually make it, as to continue further up to the pillar, it is a hard way. When one is to attempt it, a great idea is to not carry any big backpack, as I personally found out only after I had packed mine and started to bear it into the jungle, until I understood for good that it was not going to happen and I left it under a tree to pick it up on my way back. There is something like a trail leading up, though one should not really count on following it all the way. That part of the mountain is covered by thick, mossy jungle, and in order to cross through, one must get very tired, dirty and hurt. There are lots of compact thickets to push against boldly while getting profusely cut and pierced by thorns and splinters. Lots of massive fallen trunks to either clamber over or crawl underneath with chest and chin rubbing against the ground. Lots of steep, muddy passes or difficulties of any sort to somehow be negotiated... The way itself, even though the trail is not to be trusted, is fairly straightforward, as for the most part it just goes along the ridge. There is only one point where extra attention is needed, where, about half the way, two ridges coincide, with the wrong (south-north orientated) being the more apparent one when returning. About 2-3 hours after the camping one shall have made it to the spot where the pillar and a rickety Indonesian flag are to be found, at 2150 amsl.
A small fee shall be collected at a registration office in the garden premises. It is not mandatory to have a guide, though, in such a case, one should better have GPS and keen orientation skills, as one could extremely easily get lost in there and, if so, the chance to be found by anyone is minimal. The garden staff may be hired as guides and porters. I did not ask of what they'd charge, though I'm quite sure it would be reasonable, as I found them to be very genial guys.
When to Climb
All year round. Be prepared for steep slides during the rainy season.
One designated camping spot at the best viewpoint. A few more possible spots along the trail.
My account on climbing Mount Pangulubao + map