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We present the analysis of Ulysses observations of the solar wind speed (V) from 1990 to 2008. We show that the evolution of V with heliocentric distance (r) depends both on the heliolatitude and on the solar activity cycle substantially. Deviations from the predicted Parker’s profile of V(r) are so considerable that cannot be explained by an insufficiency of measurements or by other technical effects. In particular, the expected smooth growth of the solar wind speed with distance (r) is typical only for the solar activity maximum and for low heliolatitudes (lower than +/-40 ), while at high latitudes there are two V(r) branches: growing and falling. In the solar activity maximum, V increases toward the solar pole in the North hemisphere only, but in the South hemisphere it decreases with heliolatitude. In the minimum of solar activity, the profile of V at low heliolatitudes has a local minimum between 2 AU and 5 AU. This result is confirmed by the corresponding data from the other spacecraft (Voyager 1 and Pioneer 10). Unexpected spatial variations in V at low heliolatitudes can be explained by the impact of flows from coronal holes on the V(r) profile since the flows incline to the ecliptic plane. To reproduce the impact of irregularities of V in the polar corona on the behaviour of V at low heliolatitudes, we develop a stationary one-liquid ideal MHD-model at the accounting of recent results on imagery of the solar wind speed in the corona up to 5.5 solar radii obtained on the basis of combined observations from SOHO/UVCS, LASCO and Mauna Loa.