The Greater London Council (GLC) is often considered as one of the MCCs (particularly over the question of abolition), but it was a very different authority established on a different statutory basis.
The MCCs were meant to be strategic authorities running regional services such as transport, civil protection and strategic town and country planning.
The councils were all Labour Party countrolled when Margaret Thatcher's government published a White Paper entitled Streamlining the Cities which proposed their abolition, together with the abolition of the GLC.
The MCCs were to be replaced with joint boards of the existing lower tier authorities, or in some circumstances, their assets passed directly to the central government or its agencies.
The abolition of the GLC was extremely controversial, but the MCCs less so. In 1997 Tony Blair's new Labour government legislated to restore a successor body to the GLC, but not bodies have replaced the MCCs.