The Hajjar Mountains are a mountain range located in the eastern part of the Arabian Peninsula, primarily in Oman and the United Arab Emirates. They stretch approximately 700 kilometers and are known for their rugged terrain, deep valleys, and unique geological formations. The highest peak, Jebel Shams, reaches an elevation of about 3,000 meters, making it the tallest mountain in Oman. These mountains are significant for their biodiversity, hosting various plant and animal species adapted to the arid climate. The Hajjar Mountains also play a crucial role in the region's water supply, as they capture moisture from the surrounding atmosphere, contributing to local rivers and aquifers.