In a large bowl, whisk together bread flour, rye flour, salt and dry yeast.
Add water and stir with a wooden spoon. The dough should come together as a shaggy, sticky dough.
Cover and let rise for 12 to 18 hours but no longer than 24 hours.
I used parchment paper for this step rather than a tea towel. Turn the dough out onto a well-floured piece of parchment. Use a rubber spatula or bench scraper since the dough will be sticky.
Using lightly floured hands, fold the dough over, pivot the parchment paper 180° and repeat three or four times.
Turn the entire dough ball over, seam side down, and cover with plastic wrap. place on a wooden cutting board rather than leaving on a cool surface. Let rise for 2 hours.
30 minutes before the end of the second rise, move the top rack of the oven to the lower 3rd of the oven to make room for the Dutch Oven. Fire up the oven to 475° and place the Dutch Oven on the rack to preheat.
At the end of the second rise, remove the plastic wrap from the dough, remove the Dutch Oven from the oven, remove the lid. Exercise caution during this step since the oven will be extremely hot.
Using the parchment as a caddy, place the dough and parchment in the oven, replace the lid to the Dutch Oven and place it back in the oven.
Bake covered for 30 minutes then remove the cover and bake for an additional 15 to 30 minutes until the bread is a beautiful golden brown. (An internal thermometer, inserted in the center of the bread should register 200°.)