HOUSE MOUNTAIN. House Mountain stands eight miles southeast of Castell in southwestern Llano County (at 30°36' N, 98°55' W). Its summit, at an elevation of 1,828 feet above sea level, rises 530 feet above nearby Hickory Creek. The mountain has a large cave, near which many Indian artifacts have been recovered. Area topography varies from flat to rolling to steep terrain, locally dissected and surfaced variously by sandy and clay loams and shallow and stony soils. Vegetation consists primarily of open stands of live oak and mesquite.