▁symbol ▁of ▁modern ▁mount aine ering . ▁It ▁would ▁require ▁the ▁three ▁govern ments ▁of ▁Italy , ▁France ▁and ▁Switzerland ▁to ▁make ▁a ▁request ▁to ▁UN ES CO ▁for ▁it ▁to ▁be ▁listed . ▁ ▁Mont ▁Bl anc ▁is ▁one ▁of ▁the ▁most ▁visited ▁tour ist ▁destin ations ▁in ▁the ▁world , ▁and ▁for ▁this ▁reason , ▁some ▁view ▁it ▁as ▁threatened . ▁Pro - Mont ▁Bl anc ▁( an ▁international ▁collect ive ▁of ▁associations ▁for ▁the ▁protection ▁of ▁Mont ▁Bl anc ) ▁published ▁in ▁ 2 0 0 2 ▁the ▁book ▁Le ▁vers ant ▁no ir ▁du ▁mont ▁Bl anc '' ▁( The ▁black ▁hill side ▁of ▁Mont ▁Bl anc ), ▁which ▁ex poses ▁current ▁and ▁future ▁problems ▁in ▁conser ving ▁the ▁site . ▁ ▁In ▁ 2 0 0 7 , ▁Europe ' s ▁two ▁highest ▁to ile ts ▁( at ▁a ▁height ▁of ▁ 4 , 2 6 0 ▁metres , ▁ 1 3 , 9 7 6 ▁feet ) ▁were ▁taken ▁by ▁hel ic opter ▁to ▁the ▁top ▁of ▁Mont ▁Bl anc . ▁They ▁are ▁also ▁serv iced ▁by ▁hel ic opter . ▁They ▁will ▁serve ▁ 3 0 , 0 0 0 ▁ski ers ▁and ▁h ik ers ▁ann ually , ▁helping ▁to ▁alle vi ate ▁the ▁dis charge ▁of ▁ur ine ▁and ▁fa ec es ▁that ▁spread s ▁down ▁the ▁mountain ▁face ▁with ▁the ▁spring ▁th aw , ▁and ▁turns ▁it ▁into ▁' Mont ▁Mar ron '. ▁ ▁Global ▁war ming ▁has ▁begun ▁to ▁m elt ▁gla