Key Out of Time by Andre Norton — Read

It was not the general airlessness of the long-closed passage which wore on Ross's nerves, made Karara suddenly reach out and clasp fingers about the wrists of the two men she walked between; it was a crushing sensation of age, of a toll of years so long, so heavy, as to make time itself into a turgid flood which tugged at their bodies, mired their feet as they trudged after the Foanna. This sense of age, of a dead and heavy past, was so stifling that all three Terrans breathed in gasps.

Karara's breaths became sobs. Yet she matched her pace to Ashe and Ross, kept going. Ross himself had little idea of their surroundings, but one small portion of his brain asked answerless questions. The foremost being: Why did the past crush in on him here? He had traveled time, but never before had he been beaten with the feel of countless dead and dying years.