We present cosmological simulations which closely mimic the real Universe within \sim 100 Mpc of the Local Group .
The simulations , called Constrained Simulations , reproduce the large-scale density field with major nearby structures , including the Local Group , the Coma and Virgo clusters , the Great Attractor , the Perseus-Pices , and the Local Supercluster , in approximately correct locations .
The MARK III survey of peculiar velocities of the observed structures inside 80 \mbox { $h ^ { -1 } $Mpc } sphere is used to constrain the initial conditions .
Fourier modes on scales larger then a ( Gaussian ) resolution of \approx R _ { g } = 5 \mbox { $h ^ { -1 } $Mpc } are dominated by the constraints , while small scale waves are essentially random .
The main aim of this paper is the structure of the Local Supercluster region ( LSC ; \sim 30 \mbox { $h ^ { -1 } $Mpc } around the Virgo cluster ) and the Local Group environment .
We find that at the current epoch most of the mass ( \approx 7.5 \times 10 ^ { 14 } \mbox { $h ^ { -1 } $M$ { } _ { \odot } $ } ) of the LSC is located in a filament roughly centered on the Virgo cluster and extending over \sim 40 \mbox { $h ^ { -1 } $Mpc } .
The simulated Local Group ( LG ) is located in an adjacent smaller filament , which is not a part of the main body of the LSC , and has a peculiar velocity of \approx 250 ~ { } km s ^ { -1 } toward the Virgo cluster .
The peculiar velocity field in the LSC region is complicated and is drastically different from the field assumed in the Virgocentric infall models .
We find that the peculiar velocity flow in the vicinity of the LG in the simulation is relatively “ cold ” : the peculiar line-of-sight velocity dispersion within 7 \mbox { $h ^ { -1 } $Mpc } of the LG is \lesssim 60 ~ { } km s ^ { -1 } , comparable to the observed velocity dispersion of nearby galaxies .