If there were a real City of Cibola—with streets paved with gold—women would need to go there, because they have—and get—less of it.

Women still haven't reached pay parity with men, earning just 79 cents for every dollar a man makes. They spend longer periods out of the workforce, due to raising children and providing care to other family members. And to top it off, they face the prospect of needing more money in retirement than their male counterparts.

But women are running behind in retirement savings, too. They save only 7.5 percent of their salaries, compared with men who save 8.7 percent of larger salaries. They have smaller balances than men; in 2015, women had an average plan balance of $71,060, compared to men's $119,150, according to an Aon Hewitt study.