Roppongi is one of the regions of the Minato-ku area in Tokyo. At the end of the war it was requisitioned by the Allies and it became full of shopping and dining targeted to foreigners. At present it's the metropolitan area's #1 downtown destination, and is crowded during the weekend because of its many bars, clubs, and cabarets. There are numerous embassies located here, including the Spanish, Swedish, Saudi Arabian, and Micronesian, and there is also an American military facility here so there are lots of foreigners in this region. As well as that, there are bars and clubs with all kinds of international flavors. Roppongi is also one of the leading shopping centers in Tokyo even during the daytime. There's Roppongi Hills and the Tokyo Midtown complexes, where you can find everything from food to shopping and spend your whole day there. You'll also find the Mohri Garden and Hinokicho parks where you can enjoy a park even in the midst of the big city. There are also plenty of tourist spots such as the Suntory Museum of Art, Mori Art Museum, and the National Museum. Roppongi is a big place with a lot of attractions but there are concerns about its safety especially at night. The US State Department, British Embassy, and Australian Embassy all warn travelers that it can be a risky area. Do not walk alone at night, stay away from strange stores, and don't accept invitations from people you don't know.
By public transport you can reach it via the Tokyo Metro Hibiya line or the Toei Oedo line from Roppongi Station (六本木駅). By car, on the Inner Circular Route the Iikura IC (飯倉IC) is the closest interchange.