MITTE. Perhaps one of Berlin's most solemn ­ and controversial ­ sites, the Holocaust Memorial occupies a wide expanse between Brandenburger Tor and Potsdamer Platz. Exactly 2711 concrete slabs form a chilling grey grid over the area known as the Field of Stelae. The stelae represent the horrible scope of the Holocaust and are arranged at varying heights, creating a subtle wave-like appearance. Designed by NY architect Peter Eisenman, the site and its visitor center opened to the public on 12 May 2005; among those in attendance that day were several Holocaust survivors. S-BAHN: Unter den Linden or Potsdamer Platz; U-BAHN: Potsdamer Platz

MITTE. Built in 1791 as a customs collection post and recalling the design of the Acropolis's Propylaea, this formidable columned structure has served as an icon of both German factionalism and solidarity. In 1961, the Wall was built and the gate sealed off. After the Wall fell in 1989, the area was reopened to the public. The neighboring plaza is marked with merchant stalls. Located on the eastern edge of Tiergarten. S-BAHN: Unter den Linden

FRIEDRICHSHAIN. Initially 100 miles long, less than a half-mile now remains of the world-renowned Berlin Wall. The wall was built originally to divide the city from communist rule. However, its stone remnants now serve as an outdoor art gallery (called the Eastside Gallery) displaying murals painted by local and city artists. U-BAHN: Warschauerstrasse

CHARLOTTENBURG ­ WILMERSDORF. This historic broadcast tower was built in the early 1900s and offers impressive views of the forest at Grunewald and the western sector of the city. The viewing platform stands at 413 feet, and on-site dining is available in the center of the tower.

MITTE. This fascinating educational center chronicles the resistance movement to National Socialism from 1933 to 1945 via exhibits, archival material, and events. The center also oversees a memorial honoring the nearly 3000 people murdered at the Plötzensee prison from 1933 to 1945. S-BAHN and U-BAHN: Potsdamer Platz