If you visit just one secular attraction in Bucharest, make it this one; the guided tour provides excellent historical insights and is a worthwhile survey of architectural trends in Romania. Cotroceni Palace (the official residence of the president, hence the tight security) was built by Carol I in the late 19th century, and became the loveless home of Ferdinand, his nephew and adopted heir, and the young Queen Marie, but has undergone many transformations since the initial designs were executed: During Ceausescu's dictatorship it was used as the "Pioneer's Palace," where young leaders were schooled in the ways of Communism, and -- after the devastating earthquake of 1977 -- restored as a guesthouse, although it never served this function. You will pass through a host of reception rooms, sleeping quarters, and private chambers, each styled to a particular theme: the German New Renaissance dining room, private dining quarters of Carol I in Florentine style; Oriental painting room used by Queen Marie and her children; the hunting room which showcases trophies hunted by King Ferdinand, as well as bearskin rugs hunted by Ceausescu. Interestingly King Ferdinand's apartments are done out in a far more dainty, feminine style than Queen Marie's, whose quarters are quite austere -- living proof of who wore the pants in this relationship. Note: You need to phone ahead and book one of the tours, and you must bring your passport as a security deposit; ask your taxi driver to wait for you, or order a cab in advance, as the museum entrance is on a busy road in the middle of nowhere.