Maritime heritage ranges from documented wrecks and seabed remains to working harbours, naval dockyards and historic coastal landscapes. The figures below show how these assets are recorded, protected and represented internationally, with measurement dates and site boundaries kept explicit.
Contents
- England’s marine heritage record
- Legal protection and designations
- International underwater-heritage cooperation
- UNESCO maritime landscapes
- Ports, dockyards and maritime cities
- Shipwrecks and archaeological scale
England’s marine heritage record
Historic England’s National Marine Heritage Record contained 37,000 shipwreck records in English marine waters when updated on 5 August 2026. The number is a record count, not a count of confirmed wrecks visible on the seabed.
The record divides those entries by the kind of evidence available:
- About 6,000 records identify physical wreck remains on the seabed.
- About 31,000 records are known only from documentary sources.
- Approximately 7,500 records describe unidentified seabed obstructions.
- Approximately 1,000 records describe isolated findspots.
These categories describe different evidence types and should not be added together as separate wreck populations. In particular, a documentary record can relate to an event or vessel whose physical remains have not been located. The obstruction and findspot figures also describe record types within the wider marine heritage information system.
The planned coverage is broad. The National Marine Heritage Record is intended to cover English heritage assets from mean high water to the 200-nautical-mile sea limit. Historic England’s offshore data zone runs from 12 to 200 nautical miles. The record also catalogs four supporting types: activities, people, organisations and bibliographic sources. That structure places shipwrecks within a wider historical network rather than treating each site as an isolated object.
Legal protection and designations
England’s Protected wreck site dataset listed 58 protected wreck sites on 24 September 2026. The dataset draws on three statutory protection routes: the Protection of Wrecks Act 1973, the Ancient Monuments and Archaeological Areas Act 1979, and the Protection of Military Remains Act 1986. A protected-wreck count therefore reflects legal designations under several acts, not one uniform category of archaeological condition.
International maritime places may also carry multiple layers of protection. UNESCO’s site record for The Archaeological Ensemble of 17th Century Port Royal says the property is protected under two Jamaican national laws: the Jamaica National Heritage Trust Act 1985 and the Natural Resources Conservation Authority Act 1991. Port Royal received one protected-area designation in 1998 and one Protected National Heritage designation in 1999. Its World Heritage property and buffer zone have had one UNESCO Underwater Cultural Heritage protection since 9 August 2011.
Other maritime places show how designations can accumulate over time:
| Maritime place | Quantified designation history | Measurement period |
|---|---|---|
| Port Royal, Jamaica | 1 UNESCO Underwater Cultural Heritage protection; designations in 1998 and 1999 | Since 9 August 2011; 1998–1999 |
| Antigua Naval Dockyard | 1 National Park designation | Since 1984 |
| Cat Ba | 2 designations: national park and marine protected area | 1986 and 2010 |
The Antigua figure comes from UNESCO’s Antigua Naval Dockyard and Related Archaeological Sites record. Cat Ba’s two quantified designations—national park in 1986 and marine protected area in 2010—appear in UNESCO’s Ha Long Bay - Cat Ba Archipelago record. These labels concern formal protection or management status; they do not measure the total amount of heritage within each place.
International underwater-heritage cooperation
The 2001 Convention provides a global framework for underwater cultural heritage. UNESCO’s page, current in 2026, reports 81 States Parties, 12 missions by its Scientific and Technical Advisory Body, and 28 underwater-heritage capacity-building sessions. Those 28 sessions took place across four regions and reached more than 450 participants.
The Convention framework applies to cultural objects immersed for at least 100 years. That threshold helps distinguish the Convention’s underwater-cultural-heritage scope from the broader universe of modern maritime evidence and recently lost vessels. It also shows why historic wreck statistics need a clear age and legal definition before comparisons are made.
UNESCO estimates that about 10,000 First World War wrecks lie on seabeds worldwide. This is an estimate reported on 19 December 2024, rather than a complete inventory of individually identified sites. The same Heritage for Peace and Reconciliation Education Initiative ran a worldwide, five-year Dive for Peace initiative from 2014 through 2018 and a worldwide, five-year education initiative over the same period. These programme figures describe international activity, while the 10,000 figure describes estimated archaeological remains.
UNESCO maritime landscapes
Maritime heritage can cover coastlines and landscapes as well as submerged archaeology. UNESCO’s Beaches of the D-Day Landings, Normandy, 1944 property has six component parts along approximately 80 kilometres of Normandy coastline. Five are Utah, Omaha, Gold, Juno and Sword beaches; the sixth is the amphibious assault site at Pointe du Hoc. The property commemorates a multinational operation to which 17 Allied nations contributed.
The D-Day property covers 4,228.68 hectares and has a 294,749-hectare buffer zone. It includes the remains of one named artificial harbour, Mulberry B. The inscription date in the UNESCO site record is 2026, while the component sites relate to 6 June 1944. Keeping those dates separate matters: the history being commemorated and the date of World Heritage inscription are different measurements.
Another coastal urban example is the Central Zone of the Town of Angra do Heroismo in the Azores. Its maritime World Heritage property covers 212.40 hectares, based on the site record for its 1983 inscription. The same record describes a proposed buffer zone of 223.85 hectares. Because that buffer is identified as proposed in the record, it should not be read as equivalent to a confirmed current buffer boundary.
Together, these figures show the range of spatial scales used in maritime heritage: a named landing site, a chain of six coastal components, a historic urban zone and a much larger surrounding buffer. Property area and buffer area are separate measurements and should not be combined as though they represented one archaeological footprint.
Ports, dockyards and maritime cities
World Heritage records also make it possible to compare the mapped areas of port-related properties, while preserving each site’s distinct historical context.
| World Heritage property | Property area | Buffer zone or related area | Record context |
|---|---|---|---|
| Antigua Naval Dockyard | 255 ha | 3,873 ha | Inscribed 2016 |
| Port Royal | 27 ha | 292.27 ha | Inscribed 2025 |
| Qal’at al-Bahrain | 70.4 ha | Not stated here | Inscribed 2005 |
| Angra do Heroismo | 212.40 ha | 223.85 ha proposed | Inscribed 1983 |
| Liverpool Maritime Mercantile City | 136 ha | 750.5 ha | Inscribed 2004; delisted 2021 |
Sources: UNESCO records for Antigua Naval Dockyard, Port Royal, Qal’at al-Bahrain, Angra do Heroismo and Liverpool Maritime Mercantile City.
Qal’at al-Bahrain provides an unusually detailed archaeological-harbour scale. Its World Heritage property covers 70.4 hectares and its archaeological harbour comprises four main elements. The tell covers more than 16 hectares, while the sea channel covers just under 16 hectares. The sea tower lies about 1,600 metres northwest of the tell. UNESCO records nearly 4,500 years of continuous occupation, from about 2300 BC to the present.
Liverpool illustrates that World Heritage status can change. Its former maritime property covered 136 hectares and had a 750.5-hectare buffer zone. It was on UNESCO’s List of World Heritage in Danger for nine years, from 2012 through 2021, and was delisted in 2021. These are historical site-record measurements, not a claim that the property retains current World Heritage status.
Shipwrecks and archaeological scale
Individual protected wrecks show why national totals need site-level context. The Mortar Wreck site covers approximately 20 metres by 15 metres, according to its list entry, first listed on 6 June 2022. Dendrochronology dates its Irish-oak vessel to the mid-13th century. The area describes the listed site, while the date describes the vessel’s timber; neither is a count of every associated artefact.
The Axe Boat is an approximately 15-metre-long coastal sailing vessel. Survey information clarified its form in 2002, and radiocarbon dating places the remains between 1400 and 1640 AD. The range is a dating interval, not a precise launch year.
The GAD 23 wreck is a mid- to late-19th-century wooden sailing ship of about 400 tons. Historic England says fewer than 50 surviving wrecked vessels of this particular type are known in English waters. The “fewer than 50” figure is a rarity indicator for the vessel type, not the number of wrecks in the GAD 23 site.
The Stirling Castle wreck lies in approximately 15 metres of water on the Goodwin Sands. A cannon and carriage recovered from it weighed 3.5 tons in the context of a 1999 project. Another 18th-century merchant-vessel wreck lies within 55 metres of Stirling Castle’s designated area. The nearby wreck is a separate archaeological fact and should not be counted as part of Stirling Castle itself.
These cases span a 15-metre vessel, a 20-by-15-metre listed site, a 400-ton ship type and a wreck landscape containing another vessel within 55 metres. Maritime heritage statistics therefore work best when they state exactly what is being measured: a record, a designation, an area, a vessel dimension, a date range, a depth or an estimate.