In a nutshell, centre based walking holidays start and finish from the same front door. You could be setting out from a self catering apartment in Andalucia, a count's guesthouse in Transylvania, a shared, family run chalet in the French Alps or a B&B in the Balkans, but from whichever door you set off from, you'll be returning that afternoon or evening for rest, recuperation and to sample a slice of local life.
Aside from this one simple rule, centre based walking holidays can take whatever form you like. They can be tailor made to suit your preferences; they can be self-guided in as much as you have a map, walking route notes and 24hr assistance, if needed – or you can opt for guided walks in the company of an expert who knows the local area like the back of their hand. They may also include a few short transfers to get you to the start of a trail or to the next hotel, guesthouse or B&B. You might opt to share the experience with a small group of likeminded walkers, some of whom may well become part of future walking holiday plans or at least memorable stories to tell on the next trek.