Chesapeake and Potomac Telephone Company, Old Main Building

The C&P Telephone Company's construction of this main building reflected the growing importance of the telephone.

Between 1903 and 1904, the Chesapeake & Potomac Telephone Company constructed this new “Main” exchange building in a key downtown location to accommodate the increasing numbers of businesses beginning to rely on the telephone. Designed by architect Leon Eidlitz, the new building housed a complex new common battery switchboard, touted at the time as the largest in the United States. This new switchboard initially served 6,000 telephones, beginning in September 1904.

The new exchange offered a number of benefits including the elimination of multiple rings on party lines, and eliminating the need for the operator to interrupt the line to determine whether the subscriber was finished with a call or intended to receive calls.

This central exchange was the first in what would be a complex of C&P Company buildings at this location.

DC Inventory: June 19, 1985
National Register: June 13, 1988



722 12th Street, NW