Haaler Au

{{short description|River in Schleswig-Holstein, Germany}}

{{Unreferenced|date=September 2020}}

{{Expand German|topic=geo|date=October 2011|Haaler Au}}

{{Infobox river

| name =Haaler Au

| image =Unterlauf der Haaler Au.JPG

| image_size =

| image_alt =

| image_caption = Lower section of Haaler Au

| map =

| map_size =

| map_alt =

| map_caption =

| source1_location = Confluence of Reher Au and Mühlenbek between Beringstedt and Osterstedt

| mouth_location = Kiel Canal

| mouth_coordinates = {{coord|54.1857|9.5032|region:DE-SH_type:waterbody|display=it}}

| progression = {{RKiel Canal}}

| subdivision_type1 = Country

| subdivision_name1 = Germany

| subdivision_type2 = States

| subdivision_name2 = Schleswig-Holstein

| length =

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}}

Haaler Au ({{IPA|de|ˈhaːlɐ ˈaʊ̯|-|De-Haaler Au.ogg}}) is a river in Schleswig-Holstein, Germany. Before the building of the Kiel Canal the Haaler Au was a tributary of the Eider. The Kiel Canal cut the old river bed, now the Haaler Au ends at the Kiel Canal. Shortly before the Canal the river forms a lake.

The usage of canoes and rowboats is possible on the lower part of the river.