[4] The cruisers were fitted with a plough-shaped naval ram of mild steel below the waterline[5] and had a partial double bottom extending between the forward and aft magazines.

The engines were designed to produce a total of 7,500 indicated horsepower (5,600 kW) with forced draught to give the ships a maximum speed of 18 knots (33 km/h; 21 mph).

The Naniwa-class cruisers carried enough coal to gave them a range of about 9,000 nautical miles (17,000 km; 10,000 mi) at a speed of 13 knots (24 km/h; 15 mph).

[4] The main armament of the Naniwa-class ships initially consisted of two single 26-centimeter (10.2 in) Krupp cannon on pivot mounts in barbettes fore and aft of the superstructure.

The secondary armament was initially six 15-centimeter (5.9 in) Krupp cannon on pivot mounts in semi-circular sponsons on the main deck, three guns on each broadside.

Amidships, the highly-subdivided compartments formed by the sloped portion of the protective deck were filled with coal and the fore and aft areas were fitted with cofferdams to limit any flooding.

On 17 June 1888 Naniwa became the flagship of the Standing Fleet and the sisters cruised to Okinawa, Taiwan, Wonsan, Korea, and Chifu, China later that year.

[11] After taking part in the April 1890 Great Maneuvers with the Imperial Japanese Army, the cruiser was reviewed by the Emperor and then cruised off the eastern coast of Korea and visited Vladivostok in the Russian Far East during June and July.

Naniwa steamed to Honolulu, Hawaii, in early 1893 to protect Japanese citizens and interests during the overthrow of the Hawaiian monarchy by American marines and colonists and returned home in May.

Captain (later Fleet Admiral) Tōgō Heihachirō's refusal to hand the convict over to authorities from the Provisional Government nearly caused a diplomatic incident between Japan and the United States.

Naniwa arrived back in Japan on 15 April and became the flagship of Rear Admiral Tsuboi Kōzō, commander of the First Flying Squadron, on 19 July.

[15] During the Donghak Peasant Revolution, advancing rebel forces caused the Korean government request assistance from Qing China in May 1894 who began shipping troops to Asan the following month.

The Japanese government, unwilling to let Korea fall under Chinese control, began to ship troops of their own to Chemulpo (modern Incheon) that same month and occupied Chemelpo and Seoul, the Korean capital.

The Chinese cruiser was badly damaged, with her forward gun disabled, but managed to reach Weihaiwei (modern Weihai) despite being pursued by Yoshino.

Finding it empty the following morning, Itō ordered his ships to head northeast and search the area around the Yalu River estuary.

Itō believed that the Chinese ships would head for Weihaiwei and briefly searched that area the following morning before returning to the Yalu where the wreck of the Yangwei was destroyed.

Itō sent Naniwa and Akitsushima on a reconnaissance mission to Port Arthur (modern Lüshunkou) on 22 September and they were able to confirm that the Beiyang Fleet was present.

[28] Successful night attacks by his torpedo boats in early February sank or damaged the larger ships and the morale of the Chinese crews continued to decline.

Naniwa was reclassified as a second-class cruiser on 21 March 1898 and saluted Rear Admiral Prince Heinrich of Prussia, commander of the German East Asia Squadron on 29 June 1899 in Yokohama.

[36] Vice Admiral Tōgō, commander of the Combined Fleet, intended that the Fourth Division, under the command of Rear Admiral Uryū Sotokichi aboard Naniwa, reinforced by the armored cruiser Asama, would escort troop ships to Chemulpo (modern Incheon) and destroy any Russian forces there to clear the way for the IJA units to land.

[37] Chiyoda rendezvoused with Uryū's ships on the morning of 8 February and reported that the Russian protected cruiser Varyag and the elderly gunboat Korietz were anchored in the neutral port of Chemulpo, together with British, French, Italian and American warships.

[38] After the battle, the Fourth Division was tasked to protect the Korean coast between Chemulpo and Asan and to cover the movement of IJA reinforcements through the former port.

On 10 March the division ineffectually bombarded what the Japanese believed to be a naval mine control station on an island near Port Arthur.

Jessen's ships were only able to depart late the following morning and were out of radio range before they could be told that the Pacific Squadron had been defeated and returned to port.

Kamimura had kept the four armored cruisers of the 2nd Division together under his direct command and was patrolling the southern Part of the Sea of Japan when each side spotted the other around 05:00.

The senior surviving Russian officer ordered Rurik scuttled shortly afterwards and the Japanese ships began rescuing survivors.

[44][45] The following morning the Combined Fleet was widely dispersed with the Fourth Division trailing Tōgō's main body by 30 nmi (56 km; 35 mi).

Shortly after 08:00 the Fourth Division, now consisting of Naniwa, Takachiho and Tsushima, found the main body of Rear Admiral Nikolai Nebogatov's Third Pacific Squadron of damaged and obsolete battleships and coast-defense ships.

Uryū's ships closed the range down to 4,400 yd (4,000 m) before he attempted to cut ahead of the armored cuiser to prevent her from reaching her destination before dark.

As Naniwa made her turn around 20:00, she was struck by a six-inch shell from Dmitrii Donskoi that caused so much flooding that the ship had a 7° list several minutes later and was forced to disengage.