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Combining data from Gaia DR2, SDSS DR14 and LAMOST DR6, we update the fit tomodel of the properties of the stellar stream GD-1 and find that it has an ageof $\sim 13$ Gyr, [Fe/H] of $-2.2\pm 0.12$, and a distance from the sun of$\sim 8$ kpc. We tabulate 6D phase-space fiducial points along the GD-1 streamorbit over a 90$^\circ$ arc. The fitted orbit shows that the stream has aneccentricity $e \sim 0.3$, perigalacticon of 14.2 kpc, apogalacticon of 27.0kpc and inclination $i \sim 40^{\circ}$. There is evidence along the arc for 4candidate stellar overdensities, one candidate gap, two candidate stellarunderdensities and is cut off at $\phi_1 \sim 2^{\circ}$ (in the stream-aligned$(\phi_1,\phi_2)$ coordinate system of \citet{kop10}). The spur originating at$\phi_1 \sim -40^{\circ}$ implies stars were pulled away from the stream traceby an encounter (potentially a dark matter subhalo). The narrowest place ( FWHM$\sim 44.6$ pc) of the GD-1 trace is at $(\phi_1, \phi_2^c) \sim (-14^{\circ},0.15^{\circ})$, which is $\sim (178.18^{\circ}, 52.19^{\circ})$ in (R. A.,Decl.), where the progenitor is possibly located. We also find six BHB and 10BS spectroscopic stars in the GD-1 stream.

GD-1: the relic of an old metal-poor globular cluster