The Heritage Universe4 books in series
Summertide Publisher's Summary
Access to the unstable Quake was supposed to be prohibited, but some very insistent travelers were determined to make the trip. Professor Darya Lang, who studied artifacts left by the long-vanished aliens called the Builders, had a hunch that she might find the Builders themselves. Louis Nenda and the Cecropian Atvar H'sial had their own interests in Quake, and would do anything to get there. And Councilor Julius Graves was hunting murderers - if they were hiding on Quake, he would find them.
Planetary Administrators Hans Rebka and Max Perry had no choice but to go to Quake - risking their lives to protect the others - and to learn, just maybe, the secret of Summertide and the Builders.