Migration scholars in the United States (U.S.) study how migration patterns within the country relate to characteristics of migrant origins and destinations, such as political leanings or educational attainment. However, few tools exist for experts to visualize these relationships and easily share insights with students or other interested members of the general public. This data thus remains largely inaccessible to potentially interested non-experts. In this work, we present a system called Robin for visualizing U.S. county-to-county migration data in conjunction with other county-level attributes, designed to be used by experts as a communication aid or by non-experts as an exploratory tool. User studies with migration domain experts and non-experts show promising results in our efforts to support and engage both user groups.