Valenki are like big winter boots made out of wool. They are a type of footwear that people in Russia wear to keep their feet warm in the cold winter months. The wool is felted, which means that it is compressed and tangled together to form a really strong material that can protect your feet from the cold and snow.
The wool is first washed, then carded into a fluffy form and shaped into a template resembling a foot. Layers of wool are then added and glued together until it's a dense, thick mass. After that, they are either rubbed in boiling water or placed in a steam oven until they become firm and solid, which is called felting.
One of the best things about Valenki is that they are eco-friendly because the wool used to make them is biodegradable and natural. You can even wear them for many years and just replace the inner soles, so they are really durable and long-lasting.
So, in summary, valenki are woolen boots made in Russia that keep your feet warm in the winter, are made by felting wool and are eco-friendly and long-lasting.