The natural features of the islands are made up of esker forests, pristine forests and groves and the broad spectrum of flora found within them.

The most verdant forests--dry herb-rich groves--are found along the tops of the eskers, because the nutrients in the soil there has not been washed away by water. The understory vegetation includes numerous vascular plants, such as the endangered Bird’s-nest orchid, which grows in small patches.
Kelvenne’s dry, herb-rich groves are dominated by pine or spruce, while deciduous stands are made up of birch, aspen and littleleaf linden, which can be quite abundant in some places. On the ground of the herb-rich forests flower the Hepatica (Hepatica nobilis), the Lily-of-the-Valley (Convallaria majalis) and the Wild Strawberry (Fragaria vesca), around the Fly Honeysuckle (Lonicera xylosteum) and the Mountain currant (Ribes alpinum) bushes. The abundance of vetchlings (Lathyrus) and vetches (Vicia) is striking. Here and there you can see the beautiful Cinnamon Rose (Rosa majalis), the charming red Mezereon (Daphne mezereum) or the Herb-Paris (Paris quadrifolia), which lives in the shade.
On the slopes of Kelvenne, the ancient beach embankments circle round the esker at the altitude contour of about a hundred metres. Below that line grow rugged dry pine forests, typical for esker landscape.
Before the National Park was established, the forests were in commercial use, which is why the tree stand is even-aged. However, the set of esker plant species is still impressive. In the middle of Lingonberries (Vaccinium vitis-idaea) and Reindeer lichen (Cladonia rangiferina) flower the Pale-green wintergreen (Pyrola chlorantha) and the Umbellate Wintergreen (Chimaphila umbellata). There also glow the yellow Spotted Cat´s-ear (Hypochoeris maculata) and the blue groups of Harebells (Campanula rotundifolia). The Common cow-wheat (Melampyrum pratense) is a typical plant for dry forests, and its yellow flowers dominate the lower slopes of the eskers in July and August.
In many kettle holes in the esker on Kelvenne Island, the ground in the bottom has become swampy. One of the holes has turned into a small lake. Despite a few small open fens, the mires are small pine bogs, where the air is fragrant with the stunning scent of the white flowering Marsh tea (Ledum palustre).

Boating