Gitzo produce a number of tripod ranges. For something light to go on the back pack the Traveller range is ideal. The Mountaineer is a traditional style of tripod with a sliding center column, while the Systematic is a solid, modular version which is ideal for big lens work and video.
Gitzo taller systematic tripod for a very stable base for your long lens or heavier camera gear.
Gitzo Extra Tall Systematic Tripod GT5543XLS
The Giant. For the ultimate in a tall carbon fibre tripod. For when you need extra height or ultimate stability.