Rospuda Valley

The Rospuda runs north of Augustow through a valley of percolating fen - peat kept wet by groundwater moving slowly through it rather than by rain or flood - and the point about it is that this system has never been drained, which in Europe is close to unique at this size. The vegetation that depends on it is correspondingly rare: fen orchids, including the lady's slipper and the very scarce Cypripedium and Liparis, brown-moss carpets, sedge lawns that quake underfoot because the peat is floating. The valley became nationally known in the 2000s when a bypass route was planned across it and the plan was eventually changed after a long dispute involving Polish and European conservation bodies; the road now runs elsewhere and the fen was left intact. It is a place for walking the edges rather than crossing it - the ground genuinely will not hold you in the middle.

What you actually see

• An undrained percolating fen - close to unique in Europe at this size.
• Fen orchids - including species that are very scarce elsewhere.
• Quaking ground - sedge lawns floating on peat.
• A river through it - the Rospuda, with alder carr along its course.

When to go

May to July for orchids. Half a day.

Honest expectations

The ground will not carry you away from the marked edges - this is not a place to walk into. Mosquitoes are severe. There is little infrastructure and no visitor centre. Orchid sites are not signposted, deliberately.

Nearby

Augustow and its forest are south; Wigry is north-east.