A system, etc. capable of facilitating communication about a travel in which a plurality of members participate are provided. Based on communication with a first client (2a), a server (1) recognizes a plan which is determined by a departure place, a stopover, a destination, and a route and is about a first group to which a first user belongs. Based on communication with a second client (2b) of a second user belonging to the first group as a belonging-target group registered in a database (14), the second client (2b) is caused to display icons representing the departure place, the stopover, and the destination and the route included in the plan.