Around a fifth of Estonia is peatland, one of the highest proportions in the world, and the raised bog is the landscape Estonians are most attached to. It is worth understanding what you are looking at, because to an untrained eye a bog is simply a wet, empty place.
What a raised bog is
These bogs began forming after the last ice age, when lakes filled with vegetation that could not decompose in the waterlogged, acidic conditions. Layer built on layer, roughly a millimetre a year, until the peat dome rose above the surrounding water table and began to be fed only by rain. The deepest Estonian bogs are over seven metres thick, which means the surface you walk on is several thousand years old.
The result is a landscape of open ground covered in sphagnum moss, cotton grass and cranberries, dotted with dark pools and stunted pines that may be a century old and a metre and a half tall.
Where to walk
Almost every bog has a boardwalk and most have an observation tower. Viru raba in Lahemaa is the easiest and closest to Tallinn. Kakerdaja is quieter and popular for sunrise. Männikjärve, in Endla nature reserve, has one of the best towers. Soomaa has several, including bog lakes you can swim in.
All are free, all are open year-round, and the trails are marked well enough to walk without a guide.
Bog shoes
The more interesting option is a guided bog shoe walk, leaving the boardwalk entirely. Wearing what are essentially snowshoes, you spread your weight enough to cross the open bog surface, which is unnervingly soft and springs underfoot. Guides run these year-round, including at night and in winter on frozen ground. It is the one activity that makes visitors understand why Estonians talk about bogs the way they do.
Swimming and berries
Bog pools are cold, dark brown with peat, and perfectly safe to swim in where guides permit — the water is acidic and remarkably clear once you are in it.
In September the cranberries ripen and picking them is a widespread autumn activity; in late summer the cloudberries come first, further north. Estonia has everyman's right, meaning you may walk and pick berries and mushrooms on most land regardless of ownership, provided you do no damage.
Why they matter now
Peatlands store enormous quantities of carbon, and drained bog releases it. Estonia drained a great deal of peatland during the Soviet period for forestry and peat extraction, and a substantial restoration programme is now under way to block those ditches and let the water table rise again. Some of the boardwalk trails cross restoration areas, and the interpretation boards explain what is being reversed.