The HVAG's two observing sites for public programs, Telescope Row and the Halley Hill Observatory, are easily accessed from park roads.

In San Jose, from either highway 101 or highway 680, exit at the Alum Rock Avenue interchange. Go east on Alum Rock Avenue (which is also state highway 130) for 3.6 miles from route 101 or 2.2 miles from route 680. Turn right on Mount Hamilton Road (which continues state highway 130). There is a sign at this intersection indicating Grant Park. Continue on Mount Hamilton Road for 7.7 miles. This takes you over the first ridge of the mountains and into Halls Valley. Turn right at the park entrance, which is indicated by the large "Joseph D. Grant County Park" sign. If you are coming from outside of San Jose, our regional map of the Bay Area shows the location of Grant Park in relation to the major cities and highways.