Passage: This was a continuation of the work carried out in the earlier journey, this time centring on the Granite Harbour region approximately 50 miles (80 km) north of Butter Point. Taylor's companions this time were Debenham, Gran and Forde. The main journey began on 14 November, and involved difficult travel over sea ice to Granite Harbour, which was reached on 26 November. Headquarters were established at a site christened Geology Point, and a stone hut was built. During the following weeks, exploration and surveying work took place on the Mackay Glacier, and a range of features to the north of the glacier were identified and named. The party was due to be picked up by Terra Nova on 15 January 1912, but the ship could not reach them. The party waited until 5 February before trekking southward, and were rescued from the ice when they were finally spotted from the ship on 18 February. Geological specimens from both Western Mountains expeditions were retrieved by Terra Nova in January 1913.

Question: What was built at the headquarters?
stone hut