Allaine

{{Short description|River in Switzerland}}

{{Infobox river

| name = Allaine

| native_name = {{native name|fr|l'Allaine}}

| name_other = l'Allan (m, lower course)

| image = Porrentruy rivero Allaine 037.JPG

| image_caption = The Allaine in Porrentruy

| map = Allaine.png

| source1_location = Above Charmoille near Porrentruy in the Swiss Jura mountains

| source1_coordinates= {{coord|47.42939|7.23038}}

| source1_elevation = {{convert|598|m|ft|abbr=on}}

| mouth_location = Doubs near Montbéliard

| mouth_coordinates = {{coord|47.4785|6.7597|display=inline,title}}

| mouth_elevation = {{convert|335|m|ft|abbr=on}}

| progression = {{RDoubs}}

| subdivision_type1 = Countries

| subdivision_name1 = Switzerland, France

| length = {{convert|65|km|abbr=on}}

| discharge1_avg =

| basin_size = {{convert|322|km2|abbr=on}}

}}

The Allaine ({{langx|fr|l'Allaine}} {{IPA|fr|lalɛn|}} (f), in its lower course l'Allan {{IPA|fr|lalɑ̃|}} (m), ({{langx|de|Hall}}) is a 65 km long river in northwestern Switzerland and eastern France. Its source is above the village Charmoille, in the Swiss Jura mountains. Downstream from its confluence with the Bourbeuse and the Canal du Rhône au Rhin, near Méziré, it is called the Allan. It is a right tributary of the Doubs, which it joins a few km downstream from Montbéliard, where it takes the Savoureuse with it, a river with its sources in the southern Vosges.{{sandre|U23-0400}}

The Allaine/Allan flows through the following cantons, departments and towns:

• Canton of Jura (CH): Charmoille, Porrentruy
• Territoire de Belfort (F): Delle, Grandvillars
• Doubs (F): Montbéliard