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An overview of the UKHO Archive, accessing our archive and ordering copies of archive material.
As a Public Authority, the UKHO makes relevant data sets available in compliance with the ‘Infrastructure for Spatial Information in Europe’ (INSPIRE) initiative.
Our flexible service can provide tidal information tailored to your specific requirements.
We have a team of experts who specialise in technical aspects of maritime baselines, limits, zones and boundaries.
ADMIRALTY Tide Tables (ATT) format - times and heights of high and low waters, four months per page (A4 portrait)
The systematic survey of the UK’s coastal waters
How to propose a new survey, what data the UKHO requires for a nautical chart, and how to report safety critical information or errors in our products
Find out about MCA’s bathymetric data collection programme, how to share data with MCA, and guidance for offshore developers.
Times and heights of high and low waters, split into morning and afternoon, one month per page, with a table drawn around the data (A4 portrait)
Times and heights of high and low waters, split into morning and afternoon, one month per page, without a table drawn around the data (A4 portrait)
High water-only format, split into morning and afternoon, four months per page (A4 landscape)
Times and heights of high water only, split into morning and afternoon, one month per page, with a table drawn around the data (A4 portrait)
Times of high water for each day of the year, contained on one page (A4 portrait)
Hourly heights, two months per page (A4 portrait)
Times and heights of high and low waters
Times and heights of high waters only
Hourly heights
10 minute heights
Times and heights of high and low waters – alternative structure to Format 8
Times and heights of high and low waters as in Format 12, but accompanied by interval heights (any time interval from a minimum of 1 minute to a maximum of 120 minutes)
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