There's no added yeast in this bread
Just fermented rye flour water and salt.
given 24 hours to ferment and then baked for an hour
It is a bit brick like and is best toasted. Some people love the flavour of rye, others don't.
Following Andrew Whitley's recipe in "Bread Matters", his advice is that this forms the basis for a multitude of breads. I've tried this with rye wholegrains without much success, but a hybrid with wheat flour and a coating of nuts and seeds has been a hit.