The
Oberhalbstein Alps (German:
Oberhalbsteiner Alpen) or
Platta Group (Italian:
Alpi del Platta) are a mountain range in the Alps of eastern
Switzerland 
and northern Italy. They are considered to be part of the Central Eastern Alps. The Oberhalbstein Alps are separated from the
Lepontine Alps 
in the west by the
Splügen Pass 
; from the
Plessur Alps 
in the north by the river Albula; from the
Albula Alps 
in the east by the
Septimer Pass 
and the river Gelgia; from the
Bernina Range 
in the south by the
Val Bregaglia 
.
The Oberhalbstein Alps are drained by the rivers Hinterrhein, Gelgia, Liro and Mera.