This is not an exhaustive list, but hopefully will provide some inspiration.
Summer trips
- tent
- sleeping bag
- sleeping mat
- cooking equipment
- food (including some to eat on the hill)
- waterproofs (jacket and trousers)
- warm clothes (yes, it gets cold at the top of mountains and on campsites in the evening)
- water bottle
- rucksack
- walking boots
- first aid kit
- map
- compass
If you're climbing:
- climbing gear (you should know what you need...)
Winter trips
- sleeping bag
- sleeping mat (may be needed in camping barns)
- cooking equipment (may be needed in camping barns)
- food (including some to eat on the hill)
- waterproofs (jacket and trousers)
- warm clothes
- spare warm clothes
- hat and gloves
- water bottle
- rucksack
- walking boots
- first aid kit
- map
- compass
If you're climbing:
- climbing gear (you should know what you need...)
If there's ice and or snow on the hills (even if it is warm in London):
- crampons
- ice axe
- knowledge of how to use the above
