The best time to visit Kermanshah is spring (April–May) and autumn (September–October), when the Zagros mountain climate is mild and clear. Spring in particular is beautiful — the hills are green and wildflowers are everywhere. Summer brings heat to the lower valleys but the city itself, at around 1,350 metres elevation, stays cooler than the Iranian lowlands. Winters can be harsh, with snow closing mountain roads at times. Nowruz (Persian New Year, around 21 March) and the weeks following it are a popular time for Iranian domestic tourism; the monuments will be crowded.