Yermo is a continent on the planet Sanghelios, the Sangheili homeworld. The region of Iruiru was located in Yermo, at the continent's western tombolo clusters. Northern Yermo features mountain ranges and is home to the velithra. Yermo once housed the most prominent war college on Sanghelios, and still houses an armory in its Iruiru region. The renowned state of Vadam is located in the continent.
Towards the final years of the War of Beginnings, parts of the continent were attacked by the San'Shyuum Reformists when Sanghelios was invaded. Several states of Yermo were attacked, including Vadam—though, the state's keep was able to survive the attack. Vadam was once again attacked, in 2553 by the Servants of the Abiding Truth, during the Blooding Years. This conflict also saw the destruction of the continent's war college between 2553 and 2555.