Distance: 4.4 km (2.5 DOC hours) - Unmarked route, clear - Moderate terrain
Altitude: 1020m to 1724m. Gain: 308m. Loss: 722m . Gradient: 14 deg (Moderate-hard)
Skills: Occasional scrambles (3/7) - Streams (2/6)

Unmarked route, clear (7/9)
Unmarked route, follows obvious geography (river, spur, trail, etc)

Secondary, unmapped (4/5)
Route not on maps, an alternative recognised access to hut or along range / catchment

Moderate-hard (difficulty: 4/5)
Continuous moderate climbs

Moderate (difficulty: 3/5)
Low scrub in open or bush / river rocks

Occasional scrambles (difficulty: 3/7)
Tramp with some scrambles and exposure to falls

Streams (difficulty: 2/6)
Small streams, danger only in extreme weather

Unknown (difficulty: 0/7)
Not specified

The ascent to Brabazon Saddle from the south fork of Black Birch Stream is straight forward, but a bit of a slog - a 300m climb up a semi-mobile scree gully.

From the saddle descend first scree and later a bouldery creek to the forks with the main stream. Cross (a dry feet crossing in normal conditions, but potentially impassible after rain)and climb the face opposite onto the spur containing Crooked Spur Hut. Either sidle the face east on the 1100m contour, or climb to the spur and follow the crest down to reach Crooked Spur Hut 1.5km to the east.

Note: Described in the reverse direction to your journey

From Crooked Spur Hut, head north past the yards and sidle the south face of the main river valley at the height of the hut. A good terrace (possibly and old track) is reached after a bit providing a good route across the face on a gentle climb. Once above the forks, drop down good scree to the base of the creek draining Brabazon Saddle. The main creek must be crossed - and can be hopped across in normal flows, but can be impassable after rain.

The creek to the saddle is free of scrub and starts up small stable boulders - an easy scramble. Later the valley becomes open scree, but the scree is quite stable. A basin is reached about half way to the saddle - ensure you swing north to Brabazon Saddle at this point as the main valley drains Mt Caton to the west. The last 200m to the saddle are on loose, free-running scree.

The north face of Brabazon Saddle is course semi-mobile scree all the way to the valley floor. You can pick up good free running stuff just off to your right. The valley at the base of the scree face drains Tom Thumb Col to the west, and drains west to join Black Birch Creek.