From Halopedia, the Halo wiki
The Bekan quarry is a disused sandstone mining site five kilometers from the Bekan keep in the state of Mdama on Sanghelios. Beyond the quarry, there was fields used for agricultural purposes. In January 2553, the Servants of the Abiding Truth hid the frigate Unflinching Resolve in the quarry after retrieving the vessel from the Aanrar Shipyard. Jul 'Mdama, Buran 'Utaral, and Avu Med 'Telcam used the quarry as a meeting destination to discuss their rebellion against Thel 'Vadam. Later, 'Telcam retrieved the ship from the quarry to use it during the Assault on Vadam.
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