Constraints on spatial curvature from Planck alone or in combination with BAO data. The vertical dashed line indicates a spatially flat Universe, which is quite consistent with the combination of all of the observations (solid, purple filled contour). Points are coloured by the value of the Hubble constant (colour bar), dashed lines show the 68 and 95% confidence contours from the fiducial likelihood, while dotted lines show those from the alternative (CamSpec) likelihood as an indication of the systematic uncertainty.