Heiligerlee-class monitor

	Heiligerlee
Class overview
Name	Heiligerlee class
Builders	United Kingdom; Laird Brothers (2); Robert Napier & Sons (1); Netherlands; State Shipyard (Amsterdam) (2);
Operators	Royal Netherlands Navy
Succeeded by	Adder class
Completed	5
General characteristics (as completed)
Class & type	Heiligerlee-class monitor
Displacement	1,555–1,585 long tons (1,580–1,610 t)
Length	192.25–195.4 ft (58.6–59.6 m) (o/a)
Beam	44 ft (13.4 m)
Draft	9 ft 9 in (3.0 m)
Installed power	560–740 ihp (420–550 kW)
Speed	7–8 knots (13–15 km/h; 8.1–9.2 mph)
Complement	117
Armament	1 × twin 23 cm Armstrong RML ; Later replaced by single 28 cm A No. 1 breechloader;
Armor	Belt: 5.5 in (140 mm); Gun turrets: 8–11 in (203–279 mm);

The Heiligerlee-class monitors were a group of five ironclad monitors built for the Royal Netherlands Navy in the late 1860s.

Class overview
Heiligerlee
Name	Heiligerlee class
Builders	United Kingdom Laird Brothers (2) Robert Napier & Sons (1) Netherlands State Shipyard (Amsterdam) (2)
Operators	Royal Netherlands Navy
Succeeded by	Adder class
Completed	5
General characteristics (as completed)
Class & type	Heiligerlee-class monitor
Displacement	1,555–1,585 long tons (1,580–1,610 t)
Length	192.25–195.4 ft (58.6–59.6 m) (o/a)
Beam	44 ft (13.4 m)
Draft	9 ft 9 in (3.0 m)
Installed power	560–740 ihp (420–550 kW)
Speed	7–8 knots (13–15 km/h; 8.1–9.2 mph)
Complement	117
Armament	1 × twin 23 cm Armstrong RML Later replaced by single 28 cm A No. 1 breechloader
Armor	Belt: 5.5 in (140 mm) Gun turrets: 8–11 in (203–279 mm)