 The Black Cuillin , which are mainly composed of basalt and gabbro , include twelve Munros and provide some of the most dramatic and challenging mountain terrain in Scotland . The ascent of Sgùrr a ' Ghreadaidh is one of the longest rock climbs in Britain and the Inaccessible Pinnacle is the only peak in Scotland that requires technical climbing skills to reach the summit . These hills make demands of the hill walker that exceed any others found in Scotland and a full traverse of the Cuillin ridge may take 15 – 20 hours . The Red Hills ( Gaelic : Am Binnean Dearg ) to the south are also known as the Red Cuillin . They are mainly composed of granite that has weathered into more rounded hills with many long scree slopes on their flanks . The highest point of these hills is Glamaig , one of only two Corbetts on Skye . 
 The Black Cuillin , which are mainly composed of basalt and gabbro , include twelve Munros and provide some of the most dramatic and challenging mountain terrain in Scotland . The ascent of Sgùrr a ' Ghreadaidh <a href='drop_aux' title='1'><mark>is</mark></a>one of the longest rock climbs in Britain and the Inaccessible Pinnacle <a href='drop_aux' title='2'><mark>is</mark></a>the only peak in Scotland <a href='null_relcl' title='3'><mark>that</mark></a><a href='uninflect' title='4'><mark>requires</mark></a> technical climbing skills to reach the summit . These hills make demands of the hill walker <a href='null_relcl' title='5'><mark>that</mark></a>exceed any others found in Scotland and a full traverse of the Cuillin ridge may take 15 – 20 hours . The Red Hills ( Gaelic : Am Binnean Dearg ) to the south are also known as the Red Cuillin . They are mainly composed of granite <a href='null_relcl' title='6'><mark>that</mark></a><a href='been_done' title='7'><mark>has</mark></a> weathered into more rounded hills with many long scree slopes on their flanks . The highest point of these hills <a href='drop_aux' title='8'><mark>is</mark></a>Glamaig , one of only two Corbetts on Skye . 
The Black Cuillin , which are mainly composed of basalt and gabbro , include twelve Munros and provide sum of the most dramatic and challenging mountain terrain in Scotland . The ascent of Sgùrr a ' Ghreadaidh one of da longest rock climbs in Britain and the Inaccessible Pinnacle the only peak in Scotland require technical climbin skills to reach tdasummit . These hills make demands of the hill walker exceed any others found in Scotland and a full traverse of the Cuillin ridge may take 15 – 20 hours . The Red Hills ( Gaelic : Am Binnean Dearg ) to the south r also known as thdaed Cuillin . They are mainly composed of granite done weathered into more rounded hills with many long scree slopes on their flanks . Thedaghest point of dese hills Glamaig , one of only two Corbetts on Skye .