All the GPS tracks on this website have been created with a GPS watch (Suunto Ambit 2).
Unless otherwise noted, all the elevation gain/loss numbers given on this website have been corrected within SportTracks 3.1 with a data smoothing of 30sec and the plugin “Elevation Correction” configured to use the SRTM 1 database (Shuttle Radar Topography Mission).
I use such a combination because it has been shown that the most accurate elevation gain/loss profile is obtained using a GPS device with a barometric altimeter, coupled with data smoothing and elevation correction. All this leads to the least amount of error when computing elevation figures (source: La face cachée du calcul du dénivelé cumulé (D+), Author: Florent Sourbier. This document is under the “Creative Commons” license)
Example of a GPS track for which the elevation has been corrected. In this case, the discrepency is about 160 ft for a distance of 4 miles (40ft/mile)