San Marino (river)

{{Infobox river

| name = San Marino

| image =

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| source1_location = San Paolo Mountain

| mouth_location = Torello, frazione of San Leo

| mouth = Marecchia

| mouth_coordinates = {{coord|43.9632|12.3975|region:IT|display=it}}

| subdivision_type1 = Country

| subdivision_name1 = Italy, San Marino

| length = {{convert|8.7|km|mi|abbr=on}}

| source1_elevation = {{convert|864|m|ft|abbr=on}}

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The San Marino ({{Langx|it|Rio San Marino}}) is a river in the Italian peninsula. It flows through San Marino (Chiesanuova and Acquaviva), then north into Italy. For some of its length it forms part of the border between the two countries. It flows into the Marecchia at Torello, part of the commune of San Leo (Province of Rimini).