Faerie is a region of the spirit world which touches the mortal world in places. It is a realm that embodies broader concepts of nature, of which the fey and sidhe are anthropomorphic exemplars. These lands are wild and primordial, though function according to the qualities and concepts endemic of their elemental associations.
The Summer lands, for example, are like vast natural wildernesses in high summer. Life is celebrated, including the cycle of life, death, and rebirth. Wild animals roam freely through wooded dells, river valleys, and grassy plains. Every tree, flower, and blade of grass is in full bloom, fertile and full of life. Sickness is almost nonexistent. It rains in the mornings and evenings, though never obscuring the beautiful dawns and sunsets or the stars at night. The fey natives are merry. They hunt, make music, craft items of great beauty, and garden. Food is plentiful.
The lands of Winter, by contrast, are harsh and foreboding. In places there is enough free flowing water, or winter blooming foliage, to support animal life. There are wild packs and herds that cross from Summer into Winter, but packs of wolves roam the colder lands, and all manner of fierce beast preys mercilessly on those who stray too far from the herd. Everything is covered in snow or ice. Mountain ranges dwarfing all but the tallest peaks of the mortal world are frequent in these lands. Their collection of forbidding peaks and impossible cliffs providing ideal cave-dwellings for flying beasts. The fey native to this land are hungry, wicked, and, while they too make merry, it is often cruel and at the expense of others.
Larger than the Summer and Winter lands combined is that of the Wyld, which encompasses the rest of Faerie. These are the lands of fey not tied to either Court by oath or nature. It is a place both glorious and dangerous. Here the fey hunt to survive. They do so with stealth and without the ceremony or music of Summer, but also without the malice of Winter. It is composed of wilderness in autumn or spring, lands that can be plentiful in places or barren in others. There are giant shadowed forests, as well as cloud-covered plains.