{{Short description|Lake in Switzerland}} {{See also|Sources of the Rhine}} {{Infobox lake | name = Lake Toma ({{lang|de|Tomasee}}) | other_name = Lai da Tuma | image = Tomasee 2.JPG | caption = | image_bathymetry = | caption_bathymetry = | location = Grisons | coords = {{coord|46|37|57|N|8|40|20|E|type:waterbody_region:CH-GR_source:dewiki|display=inline,title}} | type = | inflow = Rein da Tuma | outflow = Rein da Tuma | catchment = | basin_countries = Switzerland | length = | width = | area = {{convert|2.5|ha|abbr=on}} | depth = | max-depth = | volume = | residence_time = | shore = | elevation = {{convert|2345|m|abbr=on}} | islands = | cities = | pushpin_map=Canton of Graubünden#Canton of Uri#Switzerland#Alps | pushpin_label_position= bottom | mapframe = yes | mapframe-zoom = 16 }} '''Lake Toma''' ({{langx|de|Tomasee}}, {{langx|rm|Lai da Tuma}} or {{lang|rm|Lag da Toma}}) is a lake at the northern face of Piz Badus, above the village of Tschamut in the canton of Grisons ({{lang|de|Graubünden}}), Switzerland. Its surface area is {{convert|2.5|ha|abbr=on}}.
It is the source of the Anterior Rhine and is deemed to be the official source of the Rhine (the source of the Posterior Rhine is above Hinterrhein, Switzerland, at {{coord|46.499|N|9.065|E|region:CH-GR_type:river|name=Source of Hinterrhein}}).
It is possible to reach the lake on a path from Oberalp Pass, suitable for most walkers although still a mountain trail.<ref>{{in lang|en}} [https://maps.graubuenden.ch/en/tour/hiking-trail/to-the-rhine-source-oberalp-pass-lake-toma/14511607/ Hike Switzerland to the source of the Rhine in Graubünden]</ref>
thumb|left|Sign for the source of the Rhine ({{langx|de|Rheinquelle}}) near Lake Toma
==See also== *List of lakes of Switzerland *List of mountain lakes of Switzerland
==References== {{Reflist}}
==External links== *{{commonscat-inline}}
Category:Lakes of Switzerland Category:Lakes of the Grisons Category:Tourist attractions in Switzerland LTomasee Category:Tujetsch
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