Westfield is located at 42°7′46″N 72°44′46″W (42.129492, −72.745986).
It is bordered on the north by Southampton, on the northeast by Holyoke, on the east by West Springfield, on the southeast by Agawam, on the south by Southwick, on the southwest by Granville, on the west by Russell, and on the northwest by Montgomery.
Westfield is split into the "South Side" and the "North Side" by the Westfield River, and the northwestern section of town is known as Wyben.

According to the United States Census Bureau, the city has a total area of 47.4 square miles (122.7 km²), of which 46.3 square miles (120.0 km²) are land and 1.1 square miles (2.8 km²), or 2.24%, are water.

Westfield is situated at the western edge of the downfaulted Connecticut River Valley where the Westfield River emerges from the Berkshire Hills and flows through the center of the city on its way to the Connecticut River some 10 miles (16 km) downstream.
Because of its large, steep and rocky upstream watershed, the river has a history of severe flood episodes, inundating adjacent parts of Westfield several times.
In spite of a complicated system of pumps, dikes, waterways, and upstream dams, Westfield lies in a floodplain zone and is still considered flood-prone.

Westfield is bordered on the east by linear cliffs of volcanic trap rock known as East Mountain and Provin Mountain.
They are part of the Metacomet Ridge, a mountainous trap rock ridgeline that stretches from Long Island Sound to nearly the Vermont border.
Both mountains are traversed by the 114-mile (183 km) Metacomet-Monadnock Trail, that also crosses the Westfield River with an ill-advised fording or a safer road-walk across the bridge at the junction of Routes 187 and 20.
The next road obstacle for hikers in
Westfield is the Massachusetts Turnpike, beneath which hikers can safely walk.

Westfield is on the fringe of the greater Northeast megalopolis—the most densely populated region of the United States—and has experienced substantial land development for suburban residential and commercial uses for the past six decades.
Yet it borders hilltowns to the west that were depopulated of subsistence farmers in the 19th century as land became readily available on the western frontier.
With population dipping below ten per square kilometer in some upland townships, forests are reverting almost to pre-settlement conditions with wild turkey, bears, coyotes and even moose returning after absences perhaps measured in centuries.
This transition over a few miles from the 21st century urbanization to population densities nearly as low as early colonial times is notable if not unique.

Westfield is located 10 miles (16 km) west of Springfield, 39 miles (63 km) southeast of Pittsfield, 95 miles (153 km) west of Boston, 30 miles (48 km) north of Hartford, Connecticut, 76 miles (122 km) southeast of Albany, New York, and 145 miles (233 km) northeast of New York City.
Westfield is located at 42°7′46″N 72°44′46″W (42.129492, −72.745986). It is bordered on the north by Southampton, on the northeast by Holyoke, on the east by West Springfield, on the southeast by Agawam, on the south by Southwick, on the southwest by Granville, on the west by Russell, and on the northwest by Montgomery. Westfield is split into the "South Side" and the "North Side" by the Westfield River, and the northwestern section of town is known as Wyben.
According to the United States Census Bureau, the city has a total area of 47.4 square miles (122.7 km²), of which 46.3 square miles (120.0 km²) are land and 1.1 square miles (2.8 km²), or 2.24%, are water.
Westfield is situated at the western edge of the downfaulted Connecticut River Valley where the Westfield River emerges from the Berkshire Hills and flows through the center of the city on its way to the Connecticut River some 10 miles (16 km) downstream. Because of its large, steep and rocky upstream watershed, the river has a history of severe flood episodes, inundating adjacent parts of Westfield several times. In spite of a complicated system of pumps, dikes, waterways, and upstream dams, Westfield lies in a floodplain zone and is still considered flood-prone.
Westfield is bordered on the east by linear cliffs of volcanic trap rock known as East Mountain and Provin Mountain. They are part of the Metacomet Ridge, a mountainous trap rock ridgeline that stretches from Long Island Sound to nearly the Vermont border. Both mountains are traversed by the 114-mile (183 km) Metacomet-Monadnock Trail, that also crosses the Westfield River with an ill-advised fording or a safer road-walk across the bridge at the junction of Routes 187 and 20. The next road obstacle for hikers in
Westfield is the Massachusetts Turnpike, beneath which hikers can safely walk.
Westfield is on the fringe of the greater Northeast megalopolis—the most densely populated region of the United States—and has experienced substantial land development for suburban residential and commercial uses for the past six decades. Yet it borders hilltowns to the west that were depopulated of subsistence farmers in the 19th century as land became readily available on the western frontier. With population dipping below ten per square kilometer in some upland townships, forests are reverting almost to pre-settlement conditions with wild turkey, bears, coyotes and even moose returning after absences perhaps measured in centuries. This transition over a few miles from the 21st century urbanization to population densities nearly as low as early colonial times is notable if not unique.
Westfield is located 10 miles (16 km) west of Springfield, 39 miles (63 km) southeast of Pittsfield, 95 miles (153 km) west of Boston, 30 miles (48 km) north of Hartford, Connecticut, 76 miles (122 km) southeast of Albany, New York, and 145 miles (233 km) northeast of New York City.
Westfield, Massachusetts