[2][3] Construction on the NT&QR out of Napanee through Yarkers to Tamworth started the same year, but was abandoned by the contractor and Rathbun had to pay the workers out of pocket.

In 1903 the final expansion was made northwestward from Tweed to connect to the Central Ontario Railway at Bannockburn, with a total of 134 kilometres (83 mi).

Hugo's son, Edward Wilkes Rathbun expanded the company's enterprises, opening a cedar mill, a flour mill and a sash, door and blind factory; he operated tugboats and lake freighters to carry cargo to Oswego, New York.

[5] At its 1895 peak, Deseronto's population reached 3338 people and Edward Wilkes Rathbun was a millionaire; an 1896 fire on the timber docks did a quarter-million dollars on damage, and the gradual depletion of natural resources (timber and minerals) on which the Rathbun business relied brought the company's activities to a halt by 1916.

The BQR was constructed in multiple segments: CNoR incorporated the BQR line into its own mainline to Smiths Falls; CN abandoned the Tweed to Bannockburn line in 1935 and Tweed to Yarker in 1941, leaving just the Smiths Falls mainline.

[7] The Bay of Quinte Navigation and Railway Company also owned the Rathbun dock in Gananoque, Ontario; it entered a contract in which that town raised $10,000 in debentures in return for a short line to be constructed from GTR's Gananoque railway station to the downtown waterfront.

[8] An 1892 McCord Museum archival photo depicts a head-on collision between two Bay of Quinte Railway engines.