9:40 a.m. My cab driver had assured me that Old San Juan is the "real" San Juan, even though it sits on its own separate island, all of it preserved in time to reflect colonial Spain. "It's not far," he had told me, hurtling us through the four-lane traffic, a Coach billboard whizzing by. I didn't believe him. Now, strolling along Luna Street, the stillness is striking. Aside from maybe a few parked cars, little here suggests that Puerto Rico's frenetic modern city is just 20 minutes away.