Little is known about the connectivity between surface water and subsurface fractures in steep permafrostaffected rock slopes. Here we present a novel high-elevation field experiment designed to monitor real-time infiltration in rock fractures at Aiguille du Midi (3842 m a.s.l), in the Mont-Blanc massif. An existing tunnel that was carved for access to visitors, allows the collection of water directly from fractures that cross the tunnel walls. We monitored the water flow rate, temperature, and electrical conductivity in two adjutant fractures. In addition we installed a fluorescence probe and inserted two different fluorescent dyes: amino-acid-G and sulphorhodamine-B, into snow patches at the surface, in two locations directly above the fractures (5-15 m) to track the water source. We sampled water from the monitored fractures and other locations in the tunnel.