Operation Grog was the name assigned to the British naval and air bombardment of Genoa

Genoa

Genoa |Ligurian]] Zena ; Latin and, archaically, English Genua) is a city and an important seaport in northern Italy, the capital of the Province of Genoa and of the region of Liguria....

 and La Spezia

La Spezia

La Spezia , at the head of the Gulf of La Spezia in the Liguria region of northern Italy, is the capital city of the province of La Spezia. Located between Genoa and Pisa on the Ligurian Sea, it is one of the main Italian military and commercial harbours and hosts one of Italy's biggest military...

 between 6 and 11 February 1941, during the Second World War.

Originally scheduled to start on 31 January 1941, the bombardment was carried out by a fleet consisting of , , and , screened by ten fleet destroyers including , , , and .
The ships left Gibraltar

Gibraltar

Gibraltar is a British overseas territory located on the southern end of the Iberian Peninsula at the entrance of the Mediterranean. A peninsula with an area of , it has a northern border with Andalusia, Spain. The Rock of Gibraltar is the major landmark of the region...

 on 6 February, with four destroyers carrying out an anti-submarine sweep whilst the heavy ships carried out a feint to deceive Italian and German observers into thinking they were supporting a convoy. Genoa

Genoa

Genoa |Ligurian]] Zena ; Latin and, archaically, English Genua) is a city and an important seaport in northern Italy, the capital of the Province of Genoa and of the region of Liguria....

 harbour was bombarded on 9 February, with the force sinking four ships and damaging 18. A targeting error by a gunnery officer on board HMS Malaya led to an armour piercing round hitting Genoa Cathedral, the shell failed to explode and remains on display there. Ark Royals aircraft attacked Livorno

Livorno

Livorno , traditionally Leghorn , is a port city on the Tyrrhenian Sea on the western edge of Tuscany, Italy. It is the capital of the Province of Livorno, having a population of approximately 160,000 residents in 2009.- History :...

 and mined La Spezia

La Spezia

La Spezia , at the head of the Gulf of La Spezia in the Liguria region of northern Italy, is the capital city of the province of La Spezia. Located between Genoa and Pisa on the Ligurian Sea, it is one of the main Italian military and commercial harbours and hosts one of Italy's biggest military...

. An attempt by the Italian fleet to intercept the British force failed, and all ships returned to Gibraltar on 11 February.