A steam-turbine including a turbine-shaft (10) aligned along a main axis (11) and including a steam inflow region (21) for superheated steam, a steam outflow region (3) and a blading zone (4) axially arranged between the inflow and outflow regions (21;3) and comprising a first part-blading zone (4a) designed in drum form and a second part-blading zone (4b) arranged axially behind the first part-blading zone (4a) and designed in chamber form. The first part-blading zone specifically has a number of reaction stages (5) each with a guide (stationary) blade structure (6) and runner blade arrangement (7).
