It took a CBS News crew more than 14 hours to drive south from Turkey to Tehran, a nearly 600-mile trip made longer by checkpoints and bad roads.

The ceasefire took hold on Tuesday, the 12th day of the war between Israel and Iran, with each side initially accusing the other of violating it until the missiles, drones and bombs finally stopped.

The U.S. Department of Homeland Security warned Americans of a "heightened threat environment" on June 22 that could include attacks on U.S. soil. That fear appeared to dissipate when Iran attacked a United States military base in Qatar June 23, injuring no one.