Often Ajanta and Ellora are twin attractions quoted synonymously. Ajanta is about 100km (62 miles) from Aurangabad. And ,Aurangabad, the base city for excursion to Ellora has a number of attractions, especially the Mughal era monuments. And Aurangabad has its series of caves similar to the more grander Ellora caves.
Pitalkhora caves, located north of Ellora is much more older site than Ellora. From a tourism point this is less publicized than the more familiar Ajanta and Ellora, and hence less crowded.
For the religiously inclined, the Grineshwar Temple close to Ellora is an important place of pilgrimage.
Daulatabad on the way to Ellora form Aurangabad has one of the most impressive forts in India.
Khuldabad , some 3km (about 2miles) before you reach Ellora has a number of Mughal era monuments including the tomb of Emperor Aurangazeb. The tropical dry deciduous forest, Gautala Wildlife Sanctuary, is located further north of Ellora.
In short, other than Ajanta and Ellora you can spend many days in Aurangabad and go for day excursions to the attractions in the region.
The tourist attractions of Ellora is spread over the 34 or so rock cut caves in a row. The centerpiece is probably the massive Kailashanatha Temple which is entirely carved out of the volcanic basalt mount.
Ajanta & Ellora are a lot larger and overwhelming than you would have imagined. A little preparation can make your sightseeing insightful, memorable, and satisfying.