Erected in 1995, these six glass towers spring up in the midst of attractions that celebrate freedom, reminding visitors of the consequences of a world without it. The pattern on the glass, which at first appears merely decorative, is actually 6 million random numbers, one for each Jew who died during the Holocaust. As you pass through, pause to read the inscriptions.

To continue on the Freedom Trail: You now pass through an area that encapsulates the benefits and drawbacks of the Big Dig. The Rose Kennedy Greenway -- the strip of parkland that runs perpendicular to this section of the Freedom Trail -- is part garden, part road, part construction site. Follow Hanover Street across the Greenway to reach the North End, which begins at Cross Street. Take Hanover Street 1 block to Richmond Street, passing the post office on your right. Turn right, go 1 block, and turn left.