In the Age of Sail, and in general before the end of World War II, gunboats were slow, weakly armored, and did not have the set of powerful weapons that main surface combatants had.

For defending gunboats, like the Dutch ones were, this put a minimum requirement on the range of their guns.

Otherwise, opposing main fleet units could simply destroy the defending gunboats from a safe range, before attacking the shore.

They then opted to use the 23 cm Armstrong rifled muzzle loading gun as its main weapon.

In turn this minimum size would allow the Dutch ships to easily retain the shallow draught that was necessary in their home waters.

In about 1875, the Dutch government concluded that the 23 cm Armstrong RML could no longer match the main guns of the fleets of their possible opponents.

1 gun would become the standard heavy weapon of the Dutch fleet in the home waters.

Each ship of the Wodan class had two compound engines with vertical cylinders.

[8] After the first boats: Wodan, Thor, Freijr, Njord, Tyr and Braga had been delivered, experiments with the propeller took place.

The Tideman model propeller gave the highest speed of 7.5 kn, and was therefore adapted.

As shown above, the selection of the 28 cm L/22 gun was the reason to design the Wodan class.

The ships of the class lost their heavy 28 cm gun when it became obsolete.