Original sentence: Abbot Pass (and the hut) may be approached from either the Lake O'Hara area on the British Columbia side (hiking past Lake Oesa, or the more technically demanding route from Lake Louise on the Alberta side
Edited sentence: Abbot Pass (and the hut) may be approached from either the Lake O'Hara area on the British Columbia side (hiking past Lake Oesa), or the more technically demanding route from Lake Louise on the Alberta side