the Merrimack above Chelmsford. By the completion of construction between Medford and Chelmsford, several extensions envisioned all along were also nearing completion. The whole system was complete in 1814, and with just a few exceptions, overall came to operate with prices and regulations as set by the proprietors of the (main) Middlesex Canal. The following extensions opened up the balance of the Merrimack River to the New Hampshire capital, Concord, which acted as a staging point for riverine traffic deep into the river system penetrating the White and Green Mountains of New Hampshire and Vermont respectively. Operation By 1808 the completed canal had reached Merrimack, NH from the Charles (the downstream terminus) and was carrying two-thirds of the down freight and one-third of the up freight to Western New Hampshire and Eastern Vermont. The other direction, the canal ran from 'Middlesex Village' or East Chelmsford, Massachusetts (The Town of Chelmsford was later divided and East Chelmsford was renamed Lowell, Massachusetts, now the fourth most populous city in Massachusetts, primarily because of the Lowell textile industry spawned by the transportation infrastructure and water power along the Middlesex Canal and the Nashua and Merrimack Rivers) through several sparser settled Middlesex County outlier suburbs such as Billerica, and Tewksbury, then closer-in suburban towns with the lower course running towards Boston generally along water courses nearly paralleling the routes of MA 38 from Wilmington, thence in Woburn along the Aberjona River from Horn Pond through Winchester (or Waterfield) into the Mystic Lakes and down the Mystic River between Arlington and Somerville on the west bank and Medford along the east (left) bank, until the river and canal ran into the Boston Harbor tidewater in the Charlestown basin. At first, it terminated in Medford, but was later extended to Charlestown, Massachusetts with a branch near Medford Center to the Mystic River. Over time, the canal was connected to by a series of other canal companies, and many of those were owned in part by the canal proprietors, which constructed spurs up through New Hampshire upstream along the Nashua and Merrimack Rivers, enabling freight to be transported as far inland as Concord, New Hampshire. Within two years of commencing operations, regular boat traffic operated by independent companies was reaching upriver over . Three main companies operated on the canal system. The water source for the canal was the Concord River at North Billerica. This was also