His face is everywhere in Cuba.

As are his revolutionary ideals.

But Fidel Castro has been noticeably absent this week during an historic break in hostilities between Cuba and the United States.

Still, he remains on the minds of many Cubans.

(SOUNDBITE) (Spanish) EUSEBIO LEAL, HISTORY EXPERT OF HAVANA, SAYING:

"We all know that in the many opportunities and as much as he may desire to, he is not there. But he knows, he is omnipresent and in everything that has happened."

Castro came to power in the 1959 revolution and became a leading ideological foe of the U.S.

In 2008, Fidel handed over power to his brother Raul, who is now overseeing this normalization of U.S.-Cuban relations.

Fidel has not been seen since January of this year.

Not even Fidel's niece, Mariela, knows where he is.

(SOUNDBITE) (Spanish) MARIELA CASTRO, FIDEL CASTRO'S NIECE, SAYING:

"No, I have no idea, no idea. But I imagine that at any moment he will wr