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The Bonnevaux Plateau is formed of a mollasic substrate that outcrops on the slopes. The rocky-clay surface formations (plateau alluvial deposits) are covered in places by loess or silt. On the whole, however, the soil is impermeable and not very fertile.

On the plateau, which dominates the Bièvre depression, agriculture has retreated and given way to stands of oak and hornbeam.

A dense drainage system has given rise to an undulating surface. All this has resulted in landscapes with limited vistas, which are set off from the main roads, are not well known.

The valleys of the Gère to the north and the Varèze to the south make this plateau a sort of wooded isle, similar to the other isles of the Dauphiné foreland, Ile Crémieu and the Chambarans Plateau . They are enclosed by narrow depressions, not more than a few hundred metres wide, which, at the level of the plateau, resemble defensive moats in which the rivers twist and turn endlessly amidst wetlands overrun by poplar groves, another rampart that is difficult to breach.

The resulting landscapes take the same overall landscape model: on the plateaus, stands of trees at Blaches and Taravas continue along from the large Bonnevaux Forest and then head to the Rhône through the woodlands of Champuy, Limone, Lille, Méraude and Dîmes; there are more or less pronounced bocages, especially to the north, that serve as transitions from the valley floors and sometimes very narrow smaller valleys, like Salle and Suzon.

There are very few villages, a dozen at most, relative to the size of the plateau. The largest group is in the north, near Vienne, in the Gère Valley: Jardin, Eyzin-Pinet, Meyssiès, Villeneuve-de-Marc, each with about a thousand inhabitants. The others, including Monstéroux-Milieu, Cour-et-Buis, are in the Varèze and the southern hills, but these are much smaller, with at most a few hundred inhabitants each. Homes are scattered here and there on the plateau interior, wherever there is no forest.

The most attractive places are those highest up, with unobstructed views. Jardin is a leading example. It is surrounded by a bocage, marked by small depressions and their streams, with beautiful open continuities of cropland, offering splendid views over the middle Gère valley. These views are much more inspiring than those onto the lower valley, which are interrupted by the entrance to the town of Pont-Evêque. Another example is Chaumont, which is located on a spur overlooking the confluence of the Gère and the Vézonne. Unfortunately, it has been so overwhelmed by housing as to undermine the accessibility needed to discover the valley.

In the interior of the plateau, Montseveroux and its chateau demand attention. The village is located on a high point and is a very inspiring point of attraction. Nevertheless, it is dominated by diffuse urbanisation, with architecture marked by the use of pisé, a non-brickwork technique using clay.