Spectra, with a radial slit in the K and Hα lines, of a sunspot close to the limb are used to determine chromospheric heights in an active region. Equidensity contours obtained with the Sabattier effect are used to measure the values of h
* for different positions in the line core and wings. The spectra have also been utilized to determine similar heights in two very restricted regions of Ca+ emission which show an arched emission structure in K232 with bright continuum emission. At the K-line centre, unit tangential optical depth in the umbra, umbra-penumbra interface, and penumbra are at 1310, 1610, and 2330 km respectively. The corresponding value for the umbra in the Hα-line centre is 1080 km. The arches have a value of h = 3000 km at Δλ = 0 for the K line.