Farther out, a ring of wide boulevards traces the fortifications built by the Moors to defend the larger city that emerged by the 12th century. The zigzags mark the bastions that jutted out at regular intervals. By the end of the 19th century, most of the walls had been demolished; the only place where you can still see the massive defenses is at Ses Voltes, along the seafront west of the cathedral.A torrent (streambed) used to run through the middle of the old city, dry for most of the year but often a raging flood in the rainy season. In the 17th century it was diverted to the east, along the moat that ran outside the city walls. Two of Palma's main arteries, La Rambla and the Passeig d'es Born, now follow the stream's natural course. The traditional evening paseo (promenade) takes place on the Born.If you come to Palma by car, park in the garage beneath the Parc de la Mar (the ramp is just off the highway from the airport, as you reach the cathedral) and stroll along the park. Beside it run the huge bastions guarding the Almudaina Palace; the cathedral, golden and massive, rises beyond. Where you exit the garage, there's a ceramic mural by the late Catalan artist and Mallorca resident Joan Miró, facing the cathedral across the pool that runs the length of the park.If you begin early enough, a walk along the ramparts at Ses Voltes from the mirador beside the cathedral is spectacular. The first rays of the sun turn the upper pinnacles of La Seu bright gold and then begin to work their way down the sandstone walls. From the Parc de la Mar, follow Avinguda Antoni Maura past the steps to the palace. Just below the Plaça de la Reina, where the Passeig d'es Born begins, turn left on Carrer de la Boteria into the Plaça de la Llotja (if the Llotja itself is open, don't miss a chance to visit—it's the Mediterranean's finest Gothic-style civic building). From there stroll through the Plaça Drassana to the Museu d'Es Baluard, at the end of Carrer Sant Pere. Retrace your steps to Avinguda Antoni Maura. Walk up the Passeig d'es Born to Plaça Joan Carles I, then right on Avenida de La Unió.