Concord grew in prominence throughout the 18th century, and some of its earliest houses survive at the northern end of Main Street. In the years following the Revolution, Concord's central geographical location made it a logical choice for the state capital, particularly after Samuel Blodget in 1807 opened a canal and lock system to allow vessels passage around the Amoskeag Falls downriver, connecting Concord with Boston by way of the Middlesex Canal. In 1808, Concord was named the official seat of state government. The 1819 State House is the oldest capitol in the nation in which the state's legislative branches meet in their original chambers. The city would become noted for furniture-making and granite quarrying. In 1828, Lewis Downing joined J. Stephens Abbot to form Abbot and Downing. Their most famous coach was the Concord Coach, modeled after the coronation coach of King George III. In the 19th century, Concord became a hub for the railroad industry, with Penacook a textile manufacturing center using water power from the Contoocook River. Today, the city is a center for health care and several insurance companies. It is also home to Concord Litho, one of the largest independently owned commercial printing companies in the country.

Based on this passage, why is concord the capital of new hampshire? Let's give stream of consciousness first:
The relevant information to answer the above question is: In the years following the Revolution, Concord's central geographical location made it a logical choice for the state capital, particularly after Samuel Blodget in 1807 opened a canal and lock system to allow vessels passage around the Amoskeag Falls downriver, connecting Concord with Boston by way of the Middlesex Canal.
So, the final answer is Concord 's central geographical location made it a logical choice for the state capital , particularly after Samuel Blodget in 1807 opened a canal and lock system to allow vessels passage around the Amoskeag Falls downriver , connecting Concord with Boston by way of the Middlesex Canal.