An apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform at least the following: receive traveller data representing polled usage of a particular traffic lane by a plurality of travellers within a particular discrete time window; use a transportation mode detection scheme to discriminate received traveller data for the plurality of travellers as conforming to a bus transportation mode wherein the transportation mode detection scheme observes the distribution of received traveller data in and around bus stop locations to discriminate received traveller data for the plurality of travellers as conforming to a bus transportation mode and designate the particular traffic lane (402, 404, 406) as a restricted-use lane based on differences in the distribution of bus-transportation-mode-discriminated received traveller data and other-transportation-mode-discriminated received traveller data, and by removing particular received traveller data which conforms to a predefined unrealistic data-set from further consideration in the designation, the designation being for use in subsequent navigation guidance. at least one processor; and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to perform at least the following: receive traveller data representing polled usage of a particular traffic lane by a plurality of travellers within a particular discrete time window; use a transportation mode detection scheme to discriminate received traveller data for the plurality of travellers as conforming to a bus transportation mode wherein the transportation mode detection scheme observes the distribution of received traveller data in and around bus stop locations to discriminate received traveller data for the plurality of travellers as conforming to a bus transportation mode and designate the particular traffic lane (402, 404, 406) as a restricted-use lane based on differences in the distribution of bus-transportation-mode-discriminated received traveller data and other-transportation-mode-discriminated received traveller data, and by removing particular received traveller data which conforms to a predefined unrealistic data-set from further consideration in the designation, the designation being for use in subsequent navigation guidance. receive traveller data representing polled usage of a particular traffic lane by a plurality of travellers within a particular discrete time window; use a transportation mode detection scheme to discriminate received traveller data for the plurality of travellers as conforming to a bus transportation mode wherein the transportation mode detection scheme observes the distribution of received traveller data in and around bus stop locations to discriminate received traveller data for the plurality of travellers as conforming to a bus transportation mode and designate the particular traffic lane (402, 404, 406) as a restricted-use lane based on differences in the distribution of bus-transportation-mode-discriminated received traveller data and other-transportation-mode-discriminated received traveller data, and by removing particular received traveller data which conforms to a predefined unrealistic data-set from further consideration in the designation, the designation being for use in subsequent navigation guidance.