  In our search for interstellar bubbles around massive stars we analyze the
environs of the O-type stars HD 38666, HD 124979, HD 163758, and HD 171589. The
location of the stars, which are placed far from the galactic plane, favors the
formation of large wind bubbles. We investigate the distribution of the neutral
and ionized gas based on HI, CO, and radio continuum data, and that of the
interstellar dust based on far infrared IRIS images. Here we report the
discovery of neutral gas cavities and slowly expanding shells associated with
the four massive stars. IR and optical counterparts were also detected for some
of the stars. We discuss the probability that the features have originated in
the action of the stellar winds on the surrounding gas.
