Important changes will begin to appear on Ordnance Survey's 1:25,000 scale Explorer map series over the next few years to incorporate new countryside access rights being phased in across England and Wales as a result of the Countryside and Rights of Way Act 2000.

The Countryside Agency and the Countryside Council for Wales are responsible for determining the extent of the new access areas, which will then require ministerial approval.

As this process is completed for each part of the country, the information will be passed to Ordnance Survey for inclusion on the appropriate Explorer maps at the earliest opportunity. On current plans, the first such maps are expected to appear in late 2004.

There has been extensive market research and field trials of various sample maps to ensure that the new maps are clear and easy to read. As a result, the way such access areas will be shown has now been agreed, as have some related changes to avoid any confusion among map readers. Under the new specification:

the extent of the new access areas will be indicated by a pale yellow tint with a pale orange border;

simplified National Park boundaries will be shown on the map cover, but not on the map itself, as the research indicated that their depiction caused confusion with access land boundaries. National Park boundaries will, however, continue to be shown on other Ordnance Survey products, including the pink-covered 1:50,000 scale OS Landranger Map series, the OS Travel Map-Tour series, and in appropriate digital map data;

civil, parish, community and other administrative boundaries will continue to be shown on Explorer maps but they will appear in magenta rather than black to avoid confusion with other features on the mapping;

those paths currently shown by black dashes will be shown with black dots instead. Subtle changes to the green rights of way symbols will make it easier to see where they coincide with these physical paths. Similar changes will be made to the orange-coloured symbols that indicate permissive paths. In Scotland, the creation of Core Paths under the Land Reform (Scotland) Act will also be reflected on Explorer maps as the information becomes available.

Over the coming months Ordnance Survey will carefully assess the extensive range of suggestions made during the market research and field trials about other ways of enhancing the look of Explorer maps and the way features are highlighted on them.

As many religious buildings are now in secular use, Ordnance Survey has also considered the way places of worship are shown on Explorer maps. It has, however, been decided not to make any changes to the way current places of worship are shown.

A spokesman said: "We will continue to use the three traditional symbols to denote three types of building. One is for a place of worship with a tower; a second is for a place of worship with a spire, minaret or dome; and a third is for a place of worship without such architectural features."

These symbols will also continue to be used for redundant churches which have not been given new uses. Former as well as current places of worship with towers, spires, minarets or domes are also helpful navigational aids. Two of the traditional symbols will be used to indicate these.

This is a new policy as far as former places of worship are concerned, so it will be necessary to make a small amendment to the map key for accuracy. To reflect the fact that some have changed their status, the description 'place of worship' in the key will be amended to read 'building/place of worship with tower' or 'building/place of worship with spire, minaret or dome'. Where a former place of worship has a new secular use but has no landmark architectural features - and is therefore of little or no help for navigation - the building will not be highlighted with the third symbol.

"This has been our policy for many years and will not change. Ordnance Survey has listened carefully to what people have said during the market research and is confident that these aspects of the new Explorer map specification will satisfy the overwhelming majority of customers," the spokesman added.

The consultation on these specific changes is now over, but Ordnance Survey always welcomes customer feedback on the content of its maps as specifications are constantly evolving.