A Ribu is a prominent mountain summit with at least 1,000 metre elevation drop all around. That is, a mountain with a topographic prominence of 1,000 metres or more.
Conceived in 2009 in Java, Indonesia, we called them the Ribus because of the Indonesian word ‘ribu’ meaning a thousand. Our site covers Ribus in the countries of Indonesia, Malaysia and East Timor.
The variety of Ribus is huge; some are easy day-hikes near large cities; others are in remote and challenging environments and require weeks of travel and hiking to reach; some are active and dangerous volcanoes.
The Indonesian Ribus stretch across the Indonesian archipelago from Aceh in the west to Papua in the east.
There are four Ribu categories, three based on their absolute elevation and a fourth ‘Spesial’ category for peaks which are considered to be of special interest. Check the Methods page for more information on the analysis of prominence.
 Sangat Tinggi |
 Tinggi Sedang |
 Kurang Tinggi |
 Spesial |
| (Very High) Over 3000 m elevation |
(Fairly High) 2000 to 3000 m elevation |
(Less High) Below 2000 m elevation |
(Non-Ribu) A special reason to bag it |
There are currently 274 Ribus, plus 132 Spesial peaks across the Indonesian archipelago.
The ‘Spesial’ category has a number of uses. Spesials are deemed of particular interest. For example Anak Krakatau is a mere 157 metres high, but is a Spesial because of its volcanic activity and great historical interest.
As of late 2020, a group of mountain lovers scattered across the globe are currently putting together a list of all the Ribus in the world, with information such as name, elevation and prominence. There may be around 7000 of them so this may take some time! Current progress can be seen at the World Ribus project website.
You may find the following two files useful in planning your hiking trips across Malaysia and the Indonesian archipelago:
An Excel spreadsheet with all the Ribus and Spesials listed, along with elevation, prominence, province, plus latitude and longitude data.
A KML file with all the Ribus and Spesials listed, for use with Google Earth.
How do I get those Tracks ?
Is the Spesial list closed, or are you considering adding new peaks?
In Papua province, only one peak is currently listed as a Spesial.
But there are a half-dozen named peaks with over 500m of prominence and 4000m of elevation, eg:
1) Ngga Pilimsit / Idenburg Pk: 4717m ele; 557m prominence / 11.1km isolation – west of the Grasberg mine, so just as hard to access as Puncak Jaya 11 km away.
2) Yamin / Prins Hendrik Pk: 4540m ele; 700m pro / 20.0km – quite isolated, “no known assents” (though my friend the MAF pilot thinks he has climbed it)
3) Cornelis Speelman Mts: 4540m ele; 700m pro / 18.2km
4) J P Coen Pk: 4500m ele; 820m pro / 63.5km – Quite prominent and isolated, certainly deserves inclusion.
*Valentijn: 4453m ele; 640m pro / 17.1km [Already listed as a Spesial, though the prominence you calculated is a bit higher]
5) Zaagtoppen (Saw Mtns): 4380m ele; 680m pro / 19.1km – As the name suggests, probably requires some rock climbing to reach the highest peak
6) Willem II Pk: 4360m ele; 620m pro / 36.9km – Quite isolated
There are also another half-dozen peaks over 4000m ele / 500m prominence that are not clearly named.
(See https://en.wikipedia.org/wiki/List_of_highest_mountains_of_New_Guinea )