Siem Reap experiences a hot and muggy tropical monsoon climate year-round, with the most popular time to visit during the dry season from November to April, which offers nice weather and fewer tourists; however, the rainy season from May to October can be just as magical, featuring abundant greenery and fewer visitors. The official currency is the Riel, though US dollars are commonly accepted throughout the nation. Most visitors need a visa to enter Cambodia, which can be obtained at land border crossings or upon arrival at the airport. Khmer is the official language, but English is widely spoken in tourist areas.