We present preliminary results from a long-term program of mapping the neut
ral absorption characteristics of the local interstellar medium, taking adv
antage of Hipparcos stellar distances. Equivalent widths of the NaI D-line
doubler at 5890 Angstrom are presented for the lines-of-sight towards some
143 new target stars lying within 300 pc of the Sun. Using these data which
were obtained at the Observatoire de Haute Provence, together with previou
sly published NaI absorption measurements towards a further 313 nearby targ
ets, we present absorption maps of the distribution of neutral gas in the l
ocal interstellar medium as viewed from 3 different galactic projections. I
n particular, these maps reveal the Local Bubble region as a low neutral de
nsity interstellar cavity in the galactic plane with radii between 65-250 p
c that is surrounded by a (dense) neutral gas boundary (or "wall"). We have
compared our iso-column contours with the contours derived by Snowden et a
l. (1998) using ROSAT soft X-ray emission data. Consistency in the global d
imensions derived for both sets of contours is found for the case of a mill
ion degree hot LB plasma of emissivity 0.0023 cm(-6) pc with an electron de
nsity of 0.005 cm(-2). We have detected only one relatively dense accumulat
ion of cold, neutral gas within 60 pc of the Sun that surrounds the star de
lta Cyg, and note that the nearest molecular cloud complex of MBM 12 probab
ly resides at the very edge of the Local Bubble at a distance of similar to
90 pc. Our observations may also explain the very different physical prope
rties of the columns of interstellar gas in the line-of-sight to the two ho
t stars epsilon CMa and beta CMa as being due to their locations with respe
ct to the Bubble contours. Finally, in the meridian plane the LB cavity is
found to be elongated perpendicularly to the Could's Belt plane, possibly b
eing "squeezed" by the expanding shells of the Sco-Cen and Perseus-Taurus O
B associations.