Hi all, I also don't like the wrong profile for bridges and tunnels, but there is nothing we can do about this so far. The other routers know that the have to treat bridges and tunnel special, but Garmin software doesn't have this information. We also cannot manipulate the elevation data because there may be another highway under the bridge or above the tunnel. Gerd ________________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von lig fietser <ligfietser@hotmail.com> Gesendet: Donnerstag, 20. Januar 2022 09:20 An: Development list for mkgmap Betreff: Re: [mkgmap-dev] elevation in bridges and tunnels I've put an example on this forum (in Dutch). The brouter route (https://tinyurl.com/3nt27szy) shows a profile that is more accurate than the route in Basecamp. https://forum.wereldfietser.nl/viewtopic.php?f=3&t=30684&p=412494#p412494 ________________________________ Van: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> namens lig fietser <ligfietser@hotmail.com> Verzonden: woensdag 19 januari 2022 23:55 Aan: Development list for mkgmap <mkgmap-dev@lists.mkgmap.org.uk> Onderwerp: [mkgmap-dev] elevation in bridges and tunnels Hi guys, I came across this video on youtube, where ridewithgps.com improved their elevation profiles by ignoring the underlying altititude data of tunnel and bridges: https://youtu.be/wd-wT3EeayI I found out that other route planners like brouter, cycle.travel and Osmand also ignores the surface altitude that lies above tunnels and underneath bridges, but mkgmap/Garmin does not. This leads to a much higher elevation gain or loss in the route profile than the actual ride. Is it possible for mkgmap to correct this issue, or is it hard coded in the Garmin Basecamp software?