"Serious hikers" refers to individuals who take hiking very seriously. They are experienced and dedicated hikers who often spend a significant amount of time exploring various trails and challenging terrains. Full definition
The ultimate challenge for serious hikers who are very fit and have experience hiking or trekking at high elevations. (nationalgeographicexpeditions.com)
The more serious hiker can visit the Drakensberg conservation areas nearby where one can do trails of varying degrees of difficulty. (umzimkuluriverlodge.com)
Let me tell you all, I have a new found respect for serious hikers. (fitfulfocus.com)