By Josh Long

Zayo Group on Friday announced an agreement to acquire 360networks holdings inc., a provider of fiber network and telecommunications services.

Louisville, Colo.-based Zayo said the acquisition of 360networks will represent the largest of 17 acquisitions since the inception of the company four years ago.

Seattle-based 360networks operates more than 18,500 route miles of intercity and metro fiber network across 22 states and British Columbia, and the company offers bandwidth infrastructure services to wireless and wireline carriers, cable providers, large enterprises and public sector customers.

The combination with 360networks marks a new chapter for Zayo, one in which we emerge as a national provider of Bandwidth Infrastructure service,” Zayo Group CEO and President Dan Caruso said in a statement. The near doubling of the network allows us to provide a greater range of solutions, both in terms of markets served and ability to interconnect services across the markets.”

Privately held Zayo Group expects the acquisition to close by early 2012 following customary approvals. Financial terms of the agreement were not disclosed.

Zayo Group is a provider of fiber-based bandwidth infrastructure and colocation and interconnection services. For the year ending June 30, 2011, Zayo Group posted revenues of $287.2 million and a net loss of $4.1 million. Investors in Zayo Group include Battery Ventures, Centennial Ventures, Charlesbank Capital Partners, Columbia Capital, M/C Venture Partners, Morgan Stanley Alternative Investment Partners and Oak Investment Partners.