When explaining public support for European integration, an important factor has been widely ignored by the literature: national borders. This chapter examines how border-related attitudes and habits affect citizens' support for different European integration policies in the Swiss-EU relationship. The analyses draw on data from a representative survey that includes citizens' opinions on the bilateral agreements, free movement of persons, cohesion billion, institutional framework agreement, and EU membership. The results show that citizens' preferences for "re-bordering", i.e., reinforcing national borders, strongly reduce support for all European integration policies. In contrast to these border-related attitudes, border-related habits - as measured by the frequency of travels across the border - only affect support for the bilateral agreements. Finally, a well-established determinant of Euroscepticism, political ideology, remains central to explaining support for integration policies: sympathisers of the nationalist-populist radical right Swiss People's Party are found to be consistently against all five selected European integration issues.