The invention provides a "hybrid" high voltage multiphase distribution substation having one or more sets of busbars including at least one air-insulated set of busbars (10), the substation having feeders (A, B, C, D) for air-insulated lines (21, 22) placed in substantially parallel bays (11, 12) on either side of the set(s) of busbars (10) and including metal-clad breaking and switching modules each formed by metal cladding (2) containing, for each electrical phase passing through a module, breaking and disconnection systems connected to a phase conductor (6) in an insulating gas, an end disconnection system (4A, 4B) being placed at each of the two ends (13, 14) of a module, the substation being characterized in that the feeders are opposite in facing pairs, and in that two opposite feeders (A, B) are electrically interconnected for each electrical phase via a single module (1) when the break systems (3A, 3B, 3C) and the end disconnector systems (4A, 4B) of said module are closed, said end disconnector systems each being connected to a respective feeder (A, B).