Subseries consists of records related to the operation of the British Columbia Coast Steamship Service, which began operating in 1903 following the 1901 purchase of the Canadian Pacific Navigation Company by the Canadian Pacific Railway Company. The records in this subseries reflect the business activities and operations of the British Columbia Coast Steamship Service and its "Princess" line of steamships, which ran passenger, freight, and ferry services along the British Columbia coast, including the popular "Triangle Route" operating between Victoria, Vancouver, and Seattle. Passenger services continued on the British Columbia Coast Steamship Services until the 1970s.

These records include log books, a captain's diary, engineering notes, contracts, memoranda, reports, payroll records and timesheets, budget summaries, invoices, inventories, technical drawings, maintenance and operation manuals, maps, sailings schedules, tickets, passenger lists, pamphlets, newspaper clippings, menus, newsletters, stationery, correspondence, photographs and photographic negatives, and artefacts such as a letter in a bottle and B.C.C.S.S. facecloths.