The Weight of Water by Anita Shreve (1997) — A dual-narrative novel built around the 1873 Smuttynose murders on the Isles of Shoals, in which a Norwegian immigrant woman survived a killer's attack that left two others dead. Shreve interweaves the historical crime with a contemporary story of a photojournalist visiting the site. The novel makes the islands and the waters off Portsmouth feel very real.
At the Sign of the Golden Compass by Eric Swanson (2007) — A novel set in early 18th-century Portsmouth, following a printer navigating the politics of pre-Revolutionary New England. The period detail is well-researched and the city's geography is recognisable.
Rambles About Portsmouth by Charles Brewster (1859) — The classic local history, written when many of the buildings Brewster described still stood and were inhabited. It reads as a series of informal walks through the city's streets, noting who lived where and what happened there. Dry in places but invaluable for anyone who wants to understand why each building matters.
Portsmouth & the Piscataqua by J. Dennis Robinson (2004) — A modern illustrated history covering the city from its founding through the 20th century, well-written and accessible, with good photographs of the historic district.