Connect your guides and staff through communities of practice
Your guides in the various European cities are valuable hubs of knowledge! They are usually popular- certainly withing pubcrawls and partytype groups and the have an optimistic quality about them.
In networks- both virtual and in real-life, optimism is seen as attractiveness. Further more, other people react to an attractive quality in a positive way. Optimists are usually more liked. Even the ones that don't like him or her, will react in a positive way, as it is strategically unwise not to, as other perceive them with a positive outlook.
They have a high-degree centrality within their networks, which means they are the local connectors, the hubs; although perhaps not the best connector to the wider network.
Organisations like yours can be made to be perceived as entities, with structures, a face of faces, local presence and be laden with attractive traits. They can alternate in being extraverted and intraverted. That requires depth! Depth you cannot give if you are too transient in your local presence.
Read "Why optimism guides your guiding"