Caradhras
Caradhras, "the Redhorn", was one of the three great peaks of the Misty Mountains that towered above the Dwarf-realm of Khazad-dûm (Moria). Tall, cruel, and cold, it was called Barazinbar in the tongue of the Dwarves and was famed for its perilous weather.
Description
Caradhras rose with its companions Celebdil (the Silvertine) and Fanuidhol (the Cloudyhead) above the deep places of Moria. Its slopes were treacherous, swept by sudden storms and deep snows, and the mountain had an ill name among travellers. Beneath it lay the Dwarrowdelf, and on its lower slopes flowed the Silverlode and other streams that fed into the Anduin.
The Redhorn Pass
The high pass over the shoulder of Caradhras, called the Redhorn Gate, was one of the few ways across the Misty Mountains in that region. During the War of the Ring, the Fellowship of the Ring attempted to cross by this pass to avoid the dark road through Moria. They were driven back by a fierce and unnatural snowstorm that buried the path and nearly destroyed them.
Whether the storm was the malice of the mountain itself, which some held to have a cruel will of its own, or the work of Sauron or other powers, was not certainly known. The failure of the attempt forced the Fellowship to take the road through Moria instead, leading to the fall of Gandalf upon the Bridge of Khazad-dûm.