Budapest is the capital city of Hungary formed from the unification of Buda, Pest, and Óbuda in 1873. It has over 1.7 million residents within its 525 square kilometers and is situated along the Danube River. Some of Budapest's most notable landmarks include Heroes' Square, Fisherman's Bastion overlooking the Danube, St. Stephen's Basilica, and the Hungarian Parliament building. The city has a long history dating back to Roman settlements and was an important political and cultural center during the Middle Ages and Ottoman rule.