The Brian Boru traces its origins to the Thames gold rush of 1867. Thames is credited with having had 112 hotels, one more than Auckland, at that time. By the 1970s this number had been reduced to seven. The hotels of the goldfields served a variety of purposes in addition to the provision of accommodation, a liquor outlet and entertainment. They provided the venues for formal public meetings held to discuss roading, bridging and wharf facilities and were the places where certain mining companies held their meetings. Accident victims were often taken to a nearby hotel for treatment. The Brian Boru Hotel was established by a Mr Sainsbury in 1867, as the Reefers' Arms. A year later it was taken over by Edmond (Ned) Twohill who had arrived at Thames before the goldrush. Twohill, originally from County Cork, renamed the establishment after Brian Boru, the Irish King (941-1014). Twohill's appointment as Treasurer of the Thames Irish National League at the inaugural meeting held 20 October 1884 confirms his commitment to his country of origin. Following his death in 1896, the licence was taken over by his widow, Kate, who had the present hotel built in 1904. The new 40-roomed hotel, capable of accommodating upwards of 70 guests at a time, replaced the less imposing two-storeyed structure which had previously occupied the site. The identity of the builder and architect is not known. The hotel was under construction in mid-July 1904. It opened for business on 5 October, 1904. The price for the newly completed building was £3,140 but this bankrupted the contractor. Eight months after completion, the hotel was extensively damaged by fire. Early on the morning of 11 June 1905, fire broke out above the kitchen in the southeastern wing. The interior of the top storey of the eastern wing was totally destroyed. The bedrooms along the Pollen and Richmond street frontages were partially burnt, requiring refurbishment. The lower floor suffered extensive smoke and water damage. By early February the following year rebuilding, renovating and furnishing the hotel had been completed. The two hotels on this site were managed continuously by members of the Twohill family from 1868 until 1974.