Costa Diadema
Costa Cruises · Cruise · In service · built by Fincantieri
Costa Diadema entered service in 2014 at 132,500 GT, the fourth and biggest ship on Fincantieri's Dream platform.
Derived metrics
Computed by ships.fyi from the core specification — see how we calculate these.
How big is it, really?
The Costa Diadema's length overall, against things you already know the size of.
The 747-8 held the longest-airliner record for over a decade, until Boeing's 777-9 took it by about 19 inches (76.72 m) — our sibling site aircraft.fyi measures everything that flies the same way.
One Costa Diadema = 1.14 Titanics · 2.9 football pitches · 12 blue whales · 4.0 Boeing 747-8s laid end to end.
Plan a sailing on Costa Diadema
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The numbers
| Length overall | ≈306 m |
|---|---|
| Beam | ≈37.2 m |
| Gross tonnage | ≈132,500 GT |
| Passengers | ≈3,724 (max) |
| Crew | ≈1,253 |
| Decks | 14 passenger decks |
| Speed | ≈22.5 kn |
| Entered service | November 2014 |
Put the Costa Diadema next to something
Last verified: 2026-07-15 · Spot an error? business@luck.fyi
What makes it different
Costa Diadema is the biggest ship ever built on Fincantieri's Dream platform, and the only one of the four that did not go to Carnival Cruise Line. She is roughly 4,000 gross tons larger than Carnival Breeze, the previous largest.
Her distinguishing feature is old-fashioned: a 500-metre outdoor promenade running the full circuit of the ship. Modern hulls tend to lose the wraparound deck to cabins and specialty venues, and Costa kept it deliberately as a Mediterranean-cruising feature.
She was the flagship for eight years until the LNG pair arrived, and remains the largest non-LNG ship in the fleet. Her name is Italian for a tiara, continuing Costa's habit of naming ships for qualities and objects rather than places or people.
The Costa Diadema line
Dream class
Il Diadema
Who operates the Costa Diadema
All 1 operator of record, verified 2026-07-15. Figures marked ≈ are approximate.
CSTCosta CruisesMediterranean itineraries from Savona; Arabian Gulf in winter.1✓→