Great Work — The locals are obsessed with completing a massive project, one that has consumed them for generations. It might be the completion of a functioning spaceyard, a massive solar power array, a network of terraforming engines, or the universal conversion of their neighbors to their own faith. The purpose of their entire civilization is to progress and some day complete the work.
Pilgrimage Site — The world is noted for an important spiritual or historical location, and might be the sector headquarters for a widespread religion or political movement. The site attracts wealthy pilgrims from throughout nearby space, and those with the money necessary to manage interstellar travel can be quite generous to the site and its keepers. The locals tend to be fiercely protective of the place and its reputation, and some places may forbid the entrance of those not suitably pious or devout.