Ascent of Jabal Mana on 2018-08-19
|Date:||Sunday, August 19, 2018|
|Ascent Type:||Successful Summit Attained|
| Location:||Saudi Arabia|
| Elevation:||8858 ft / 2699 m|
Ascent Trip ReportEric and Matthew Gilbertson
Aug 17 – arrive in Abha, hike up Jabal Sawda (N 18.266717°, E 42.368264°)
Aug 18 – hike up Jabal Ferwa (N 17.928547°, E 43.265528°)
Aug 19 – Drive to Tanomah, climb possible first ascent up north ridge of Jabal Mana (5.4), return to Abha
Aug 20 – flight back to US
Until 2018, it was widely believed that Jabal Sawda was the tallest mountain in Saudi Arabia. However, after taking measurements on both peaks with an accurate GPS unit in August, we can now report with confidence that Jabal Ferwa is the true highpoint, and is about 3 meters taller than Jabal Sawda.
Other than our measurements, almost all existing publicly-availably sources give different elevations for Jabal Sawda, and it appears that until now it has never actually been surveyed carefully enough to definitively say whether it is the highest point in the country.
According to SRTM data (satellite-based elevation measurements), Jabal Sawda lies between the 2980m and 3000m height contours. However, there is one (and only one) other peak in Saudi Arabia, Jabal Ferwa, commonly considered the second highest mountain, which also lies between the 2980m and 3000m contours on SRTM data. SRTM elevations have errors up to 16m (source: https://www2.jpl.nasa.gov/srtm/statistics.html), thus SRTM data alone is not accurate enough to determine which of these two peaks is the highest.
I discovered, doing some background research, that several land-based topographic surveys have been conducted in
Saudi Arabia over the past few decades, and the results are publicly available, for a small fee, on mapstor.com. The Soviets conducted a survey in 1978 and measured Jabal Sawda to have an elevation of 3032m and Jabal Ferwa to have an elevation of 3091m.
The US military also conducted a survey, the j06-c (date unclear), and measured Jabal Sawda to be 3015m tall and Jabal Ferwa to be 3020m tall. These were the only publicly-available surveys that measured both peaks.
The UK military joint operations graphic from 1986 measured Jabal Sawda to have an elevation of 3015m, but did not measure Jabal Ferwa. The US Military NE38 (date unclear) measured Jabal Sawda at 2910m, but also did not measure Jabal Ferwa.
It appeared, from all the data I could find, that no source definitively measured Jabal Sawda as taller, while several sources measured Jabal Ferwa as taller, and one source (SRTM) measured them as equal height within the margin of error of the measurement.
This data calls into question whether Jabal Sawda is the true highest point in Saudi Arabia. Matthew and I learned through a GIS specialist friend, that there now exist survey-grade GPS units which can theoretically measure elevation to 10cm accuracy, if brought to the summit of the mountain and the data is carefully post-processed with data from a nearby base station. If we could just acquire one of these units and bring it to each summit, we thought, we could definitively determine which mountain is the true highpoint of Saudi Arabia...
Link to full trip report and pictures.
This page has been served 91 times since 2005-01-15.