01-27-2012, 05:36 AM
There are regularly scheduled free escorted summit tours offered at the Onizuka Visitors Center every Saturday & Sunday, that include tours of at least one observatory. You may want to check out this link & see if you can get more info on a weekday tour:
http://www.ifa.hawaii.edu/info/vis/
http://www.ifa.hawaii.edu/info/vis/