CyrusOne Halfweg (AMS1) data center, Halfweg, North Holland

CyrusOne operates its AMS1 data center at Linieweg 1 in Halfweg, Netherlands, on the PolanenPark business park between Haarlem and Amsterdam, about 15 minutes from Amsterdam and 10 from Schiphol Airport. The campus is designed for 54 megawatts of power across two buildings of 27 megawatts each, with 29,350 square meters of technical space, according to the company.

CyrusOne bought 6.3 hectares of land at PolanenPark from the Schiphol Area Development Company, which said the site would hold about 72 megawatts across two buildings. The Belgian contractor Cosimco began building the first building, a three-story, 27,000-square-meter shell, in December 2018 and made it wind and watertight within five months.

CyrusOne, the city of Haarlem, the province of North Holland, and local utilities Waternet and Alliander DGO studied whether the data center's waste heat could feed a heating network in Haarlem; as of 2019 those talks were still ongoing. The project is part of the European Green IT innovation initiative Catalyst.

Halfweg was CyrusOne's second large expansion in the Netherlands, after a partnership with Agriport A7 in Middenmeer, 40 kilometers north of Amsterdam, for a 270-megawatt campus.