We apply a simple axisymmetric disc model to 218 Galactic Cepheids whose accurate measurements of the distance and velocities are obtained by cross-matching an existing Cepheids catalogue with the Gaia DR2 data. Our model fit determines the local centrifugal speed, $V_mathrm{c}$ $-$ defined as the rotation speed required to balance the local radial gravitational force $-$ at the Suns location to be $V_{c}(R_0)=236pm 3$ km s$^{-1}$ and the Suns azimuthal and radial peculiar motions to be $V_{odot}=12.4pm0.7$ km s$^{-1}$ and $U_{odot}=7.7pm0.9$ km s$^{-1}$, respectively. These results are obtained with strong priors on the solar radius, $R_0=8.2pm0.1$ kpc, and Suns angular rotation velocity, $Omega_{odot}=30.24pm0.12$ km s$^{-1}$ kpc$^{-1}$. We also applied the axisymmetric model to mock data from an N-body/hydrodynamic simulation of a Milky Way-like galaxy with a bar and spiral arms. We find that our axisymmetric model fit to the young stars recovers the local centrifugal speed reasonably well, even in the face of significant non-axisymmetry. However, the local centrifugal speed determined from our Cepheid sample could suffer from systematic uncertainty as large as 6 km s$^{-1}$.
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