Mountain rescuers have again warned people to be prepared before tackling Snowdon after rescues over the bank holiday weekend.
An artists impression of the new summit building
Llanberis Mountain Rescue Team had to rescue a 60-year-old diabetic after he missed the last train back down.
A 26-year-old woman broke her ankle as she tried to walk down with a party, who had "totally unsuitable footwear".
Rescuers warned problems could worsen with rail timetable changes when the old summit building is demolished.
"People really should check before starting out and not depend on the train," said Dr Gwyn Roberts, chairman of the Llanberis Mountain Rescue Team.
He said the diabetic walker "overstretched himself" on the ascent and then had to call for help when he realised he had missed the last train down.
"There will be even less facilities on the summit whilst the work is going on the summit and it will last around 18 months which takes us through all of next summer," Dr Roberts added.
In another incident, the team rescued a woman who had taken the train up the mountain but then fell and broke her ankle as she attempted to walk down.
"She was with a party who were not equipped to walk in the mountains, their footwear was totally unsuitable" said Dr Roberts.
Low cloud problem
Because of problems with low cloud, 25 members of the Llanberis team took five hours to stretcher the casualty down the mountain.
Another party of parents and two children, who had stopped to help the injured woman, then had to be helped themselves.
One of the children had to be airlifted from the mountain suffering from the effects of the cold.
"This again shows how severe the weather can be on the mountain even in August," said Dr Roberts.
The Snowdon Mountain Railway are warning on their website about changes to their time table due to the demolition work.
From 4 September trains will terminate at around 2,500ft (762m) at either Clogwyn or Rocky Valley.