So the word didn't exist in English until it was imported to describe a subject of painting, which generally had to be picturesque. The tradition of landscape painting arose in Protestant countries because religious subjects for painting were no longer in vogue (because they were regarded as idolatry); though religious paintings set in landscape had existed earlier, depictions of just countryside views came later.
Landscape, first recorded in 1598, was borrowed as a painters' term from Dutch during the 16th century, when Dutch artists were on the verge of becoming masters of the landscape genre. The Dutch word landschap had earlier meant simply 'region, tract of land' but had acquired the artistic sense, which it brought over into English, of 'a picture depicting scenery on land'.
Archaeologists view landscape as a palimpsest. It has been modified over and over again by successive use; different farming processes, quarrying, building, industry and so on have created layers of use and re-use, as in the successive human interactions with Dartmoor. There is also a whole style of archaeology called landscape archaeology, which deals with human interactions with the landscape and their impact upon each other.
Historians view landscape almost as a memory theatre. Simon Schama's magisterial and entertaining work, Landscape and Memory (1995) shows how the symbolism of landscape (specifically rivers, mountains and forests) has changed over the centuries.
Some Pagans view landscape as a timeless whole, intimately connected with ancestors, and containing the song of the ancestors to be accessed by shamanic vision. Some would regard the landscape as having agency in the form of land-wights or spirits of place.
Others might have a more dualistic view (but still consistent with the immanence of spirit in the physical world) where spirit is immanent in the landscape, but not identical with it. (Correspondingly in this view, the human spirit leaves the bones after death and goes somewhere else, maybe to an Otherworld that is only a heartbeat away from this world, or entwined with it as the faery realms and extra dimensions are said to be.)
Others still might take a view closer to historical and archaeological perspectives, regarding our sense of historical place in the landscape and our memories of the dead as something that informs our identity, our sense of who we are, and wanting to recover the stories of the ancestors and the landscape through archaeological and historical means (since shamanic visions are all very well but tend to be unverified personal gnosis).
Chas Clifton, in his excellent article Nature Religion for Real (1998), suggests some great ways to get closer to your local landscape or bioregion by finding out about its wildlife, plants, sacred sites, soil type, geology, and so on. I have written an article about Magical attunement to a new home (2002), which suggests magical techniques for connecting with landscape, and also has suggestions for further reading.
What does landscape (or the land) mean to you? Do you feel connected with the landscape (or the land)? How?