Bidean nam Bian is the highest point in the traditional county of Argyll in Scotland, lying to the south of Glen Coe. It is a complex mountain, with many ridges and subsidiary peaks, one of which, Stob Coire Sgreamhach, is classified as a separate Munro.

The most noticeable features of Bidean nam Bidean are the famous Three Sisters of Glen Coe, three peaks (in reality simply the steep ends of ridges) that face north into the Glen. Two of the sisters, Gearr Aonach (Short Ridge) and Aonach Dubh (Black Ridge) converge at Stob Coire nan Lochan, a 1115 m subsidiary peak of Bidean that lies about 1 km to the northeast of the actual summit. The final, most easterly sister, Beinn Fhada, joins the Bidean massif at the summit of Stob Coire Sgreamhach.

Beinn Fhada is separated from Gearr Aonach by a glen known as Coire Gabhail. This translates to Glen of Capture, however the glen is more normally known as the Hidden or Lost Valley. Either name may be considered appropriate since it is believed that in former times the valley was used by members of Clan Macdonald to hide stolen cattle. The glen is ideal for this purpose since it is bloked by a glacial landslip, and from Glen Coe appears as a narrow gorge. In fact, once past the landslip the floor of the glen is wide and flat – ideal for cattle. The path from Glen Coe through the gorge into Coire Gabhail is a popular short walk (around 4 km in total), though it is rough in places.

There are several routes up Bidean nam Bian. One may continue from the hidden valley, reaching the main ridge by means of zig-zag path that climbs through scree at the head of the corrie. From here one may also climb Stob Coire Sgreamhach which lies only about 0.5 km to the southeast.

Other routes include ascending Stob Coire nan Lochan and then using the connecting ridge to reach the main summit, or ascending via the Allt Coire nam Beitheach and following either branch of this burn to reach the main ridge either side of the subsidiary peak of Stob Coire nam Beith, which lies about a kilometre to the west of the main summit.

All of the above routes start from Glen Coe, and may thus be combined to allow a traverse of the mountain. Due to the accessibility of Bidean from the north, routes on the southern side are used much less frequently.