1. Advanced Telecom Services 1919 Lansdowne Rd, Halethorpe, MD 21227 Coordinate: 39.25274,-76.66696 Phone: (410) 644-5000
2. Telecom Networks, LLC 919 Niagara Ct, Halethorpe, MD 21227 Coordinate: 39.23672,-76.65164 Phone: (410) 242-7980