Map; pocket Underground map, issued by TfL, December 2018

The document is printed on both sides in multiple colours, on paper that is folded into 4 sections. The cover artwork depicts artificial lips and teeth held inside someone's mouth, and displayed upside down. The diagrammatic map occupies three sections. An index of stations occupies two sections on the reverse side. The principal change to the map since the previous May 2018 edition arises due to a new symbol. This is a small broken black line drawn between two interchange stations (i.e. between black open circles); this broken line indicates it is 'under a 10 minute walk between [the two] stations'. Some station pairs that were previously shown as interchange stations have been demoted to 'up to a 10 minute walk'. For example: Tower Hill & Gateway; West Hampstead Bakerloo and Overground; Walthamstow Queen's Road and Central. Some previously unlinked stations are now linked by a 10 minute walk: for example Camden Town and Road; South Wimbledon and Morden Road; New Cross and Gate. This has necessitaated some realignment of the diagrammed tracks. The 'check before you travel' list of stations has been updated.