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We explore the vicinity of the Milky Way through the use ofspectro-photometric data from the Sloan Digital Sky Survey and high-qualityproper motions derived from multi-epoch positions extracted from the Guide StarCatalogue II database. In order to identify and characterise streams as relicsof the Milky Way formation, we start with classifying, select, and study $2417$subdwarfs with $\rm{[Fe/H] < -1.5}$ up to $3$ kpc away from the Sun as tracersof the local halo system. Then, through phase-space analysis, we findstatistical evidence of five discrete kinematic overdensities among $67$ of thefastest-moving stars, and compare them to high-resolution N-body simulations ofthe interaction between a Milky-Way like galaxy and orbiting dwarf galaxieswith four representative cases of merging histories. The observed overdensitiescan be interpreted as fossil substructures consisting of streamers torn fromtheir progenitors, such progenitors appear to be satellites on prograde andretrograde orbits on different inclinations. In particular, of the fivedetected overdensities, two appear to be associated, yelding twenty-oneadditional main-sequence members, with the stream of Helmi et al. (1999) thatour analysis confirms on a high inclination prograde orbit. The three newlyidentified kinematic groups could be associated with the retrograde streamsdetected by Dinescu (2002) and Kepley et al. (2007), whatever their origin, theprogenitor(s) would be on retrograde orbit(s) and inclination(s) within therange $10^{\circ} \div 60^{\circ}$. Finally, we use our simulations toinvestigate the impact of observational errors and compare the current pictureto the promising prospect of highly improved data expected from the Gaiamission.

New Signatures of the Milky Way Formation in the Local Halo and Inner Halo Streamers in the Era of Gaia