The Unteraargletscher (German pronunciation: [ʔʊntərʔɑːrglɛtʃər]), literally "Lower Aare-Glacier", is the larger of the two sources of the Aare river in the Bernese Alps. It emerges from the association of the Finsteraargletscher (near the Finsteraarhorn) and the Lauteraargletscher (near the Lauteraarhorn) and flows for about 6 km (3.7 mi) to the east down to the Grimselsee near the Grimsel Pass. In total the glacier is 12.95 km (8.05 mi) long and 29.48 km² (11.38 sq mi) in area (1973).