Top o'Selside is a hill in the Lake District in Cumbria, England. At 335 metres (1,099 ft), it is the highest point of the group of hills situated between Coniston Water and Windermere. This group also includes the Wainwright of Black Fell and the summits of Black Brows and Rusland Heights. Top o'Selside lies not in the centre of this region, but in the south-western corner, just outside the forestry plantations of Grizedale Forest and only two-thirds of a mile from the eastern shore of Coniston Water. This large separation from any higher ground gives it enough relative height to make it a Marilyn.