Transylvania is the largest region of Romania. It is also the westernmost region, the most prosperous, and perhaps the best known.
Even though many people know it for being a land of bloodthirsty vampires and never-ending forests, Transylvania is, in terms of natural beauty, the best Romania offers. Transylvania is certainly one of the most beautiful natural regions in Europe, and all this is offered at a price far below that of, say, Germany or France.
And if you're not into mountains, forests and landscapes, Transylvania has all the history and culture you want - from medieval fortress towns and monasteries to lively cities with stunning Baroque architecture.
Although now part of Romania, the history of Transylvania has more to do with Hungary and the former Austro-Hungarian Empire.
Nowadays, everyone in Transylvania speaks Romanian, though for many of the ethnic Hungarians -- about 12% of the population, but far more in certain areas -- Hungarian is actually their first language. Few native German-speakers remain, but in any sizeable town you should be easily able to find people who speak at least moderately good English, French, or German.
Transylvania is relatively easy to access, due to its relative economic prosperity, tourism industry and proximity to Western Europe.
Transylvania is not a land of dangers lurking around each darkened corner. It houses a relatively large bundle of police headquarters, so that if anything goes amiss in your journey, help will be close by.