Costa Diadema is a Dream-class cruise ship owned by Carnival Corporation and operated by Costa Crociere. At her time of delivery, Costa Diadema was the largest vessel to fly an Italian flag and was Costa's largest vessel at the time; she was formerly Costa Crociere's flagship being replaced by the Costa Toscana in 2022. Costa Diadema entered service in 2014. Costa Diadema is a Dream-class cruise ship operated by Costa Cruises. This SeaDays guide lists verified catalog facts so you can compare Costa Diadema with other Costa Cruises ships before booking.
Costa Diadema Cruise Ship Guide
Costa Cruises · Dream-class cruise ship
Ship planning snapshot
Costa Diadema at a glanceCosta CruisesDream-class cruise shipSeaDays guide
Overview
Key facts
- Cruise line
- Costa Cruises
- Ship class
- Dream-class cruise ship
- Entered service
- 2014
- Gross tonnage
- 132,500 GT
- Passenger capacity
- 3,700 (lower berth / double occupancy)
- Crew
- 1,253
- Length
- 306 m
- Beam
- 37 m
What makes this ship notable
Costa Diadema is a Dream-class cruise ship owned by Carnival Corporation and operated by Costa Crociere. At her time of delivery, Costa Diadema was the largest vessel to fly an Italian flag and was Costa's largest vessel at the time; she was formerly Costa Crociere's flagship being replaced by the Costa Toscana in 2022.
Highlights
- Costa Diadema is a Dream-class cruise ship owned by Carnival Corporation and operated by Costa Crociere.
- At her time of delivery, Costa Diadema was the largest vessel to fly an Italian flag and was Costa's largest vessel at.
Practical planning
Use Costa Diadema’s catalog specs—capacity, year, and class—to judge whether the ship matches your itinerary length and travel party. Cabin location, dining reservations, and show times are published by Costa Cruises for each sailing; confirm those on your booking rather than assuming sister ships are identical. SeaDays helps you keep port days, sea days, and notes for Costa Diadema in one place so planning stays with the voyage instead of scattered screenshots.
Frequently asked questions
What cruise line operates Costa Diadema?
Costa Diadema is operated by Costa Cruises.
When did Costa Diadema enter service?
Costa Diadema entered service in 2014.
What class is Costa Diadema?
Costa Diadema is a Dream-class cruise ship.
How many passengers does Costa Diadema carry?
Catalog capacity is 3,700 (lower berth / double occupancy). Figures can vary by cabin configuration.
How large is Costa Diadema?
Verified catalog specs list Costa Diadema at 132,500 GT, 306 m long, 37 m beam.
Does SeaDays publish passenger reviews for Costa Diadema?
This page is a catalog guide, not a review. Community reviews live in the SeaDays app when guests have submitted them.
Related ships
- Costa Toscana cruise ship guide
- Costa Smeralda cruise ship guide
- Costa Fascinosa cruise ship guide
- Costa Favolosa cruise ship guide
- Costa Deliziosa cruise ship guide
Related ports
What is a sea day? · First-time cruise tips · Ports directory
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