Comms kit takes to the Alps for ultramarathons

The organisers of the PTL used a Google Earth overlay to keep track of participants. Each team was issued with a GPS module — and four spare battery packs to give five days' potential use — which sent a text message to the control room every 15 minutes. The message contained a team identifier, date and time, GPS position and elevation.

As with the UTMB, each participant carried a mobile phone, so organisers could contact them if they were judged to have veered too far from the roughly defined course. The organisers could also have contacted participants to alert them of impending trouble, such as inclement weather or an imminent cliff.