And if you go down on the map page to where it says "choose a map" then other types of map can be accessed and viewed in same way. For example is you go to "OS 25inch" (or https://maps.nls.uk/geo/explore/#zoom=17&lat=52.5022&lon=-1.8697&layers=168&b=1) then you get a slightly higher resolution map, or you can highlight railways or land use.