Complex sentence: Together with British alpinists such as Mummery, A. W. Moore and D. W. Freshfield, Dent was involved in the pioneering of climbing in the Caucasus, where he made the first ascent of Gestola (4,860 m) with W. F. Donkin in 1886.
Split into simpler sentences: Together with British alpinists such as Mummery, A. W. Moore and D. W. Freshfield, Dent was involved in the pioneering of climbing in the Caucasus. Dent made the first ascent of Gestola (4,860 m) with W. F. Donkin in 1886.