The gravel begins where the comfort ends. Above Himeville the tar gives out and the Sani Pass road takes over, climbing along the valley of the Mkhomazana River toward the high wall of the Drakensberg. This is the lower part of the pass, close to the South African border post, and it is the stage where you find out how your bike likes loose stones, water crossings and ruts, before the real gradient starts.
The surface is the main thing to think about. It is rough, with embedded rock, patches of deep gravel and washouts after rain, and the road narrows as it goes up. Riders who know it set their tyre pressures lower, stand on the pegs and keep their speed modest, and the ones who get into trouble are usually those who try to ride it like a tarmac road. Four-by-fours share the track, and the sound of a diesel engine echoing up the valley is your cue to keep to your side.
The valley is lovely in a rugged way. Grassy slopes rise on both sides, dotted with proteas and the yellow flowers of the high grassland, and the first buttresses of the escarpment come into view ahead, dark basalt capped with mist. The Drakensberg is a World Heritage site, and the rivers that rise here feed much of KwaZulu-Natal. Look for rock hyrax on the stones and black eagles overhead.
Before you commit, there are formalities. The South African border post checks passports and, since you are heading into the Kingdom of Lesotho, you should carry your passport, vehicle registration and proof of insurance. Opening hours are limited, and the pass is not a place to arrive late in the day, because the climb takes longer than you would expect and the weather can turn quickly.
Fuel is not available here. Underberg and Himeville, a short ride back, are where riders fill up and where the last cafes and shops sit. Pack water, warm layers and a rain jacket, because the temperature drops sharply with altitude and even a summer morning can turn wet and cold.