The Hubble Flow Why Does the Cosmological Expansion Preserve its Kinematical Identity from a Few MPC Distance to the Observation Horizon?

The problem of the physical nature of the Hubble flow in the Local Volume ($D < 10$ Mpc) stated by Sandage(1986, 1999) is studied. New observational data on galaxy motions and matter distribution around the Local Group and nearby similar systems are described. Dynamical models are discussed on the basis of the recent data on cosmic vacuum or dark energy.