The Challenger-class cruisers were essentially repeats of the previous Highflyer class, albeit with more powerful propulsion machinery.

The boilers were designed to produce enough steam to allow the engines to reach 12,500 indicated horsepower (9,300 kW).

[2] The ships easily exceeded their designed power and speeds during their sea trials.

[1] The main armament of the Challenger class consisted of 11 quick-firing (QF) 6-inch (152 mm) Mk I guns.

[3] The ships' protective deck armour ranged in thickness from 1.5 to 3 inches (38 to 76 mm).