Proença-a-Nova, Castelo Branco (Portugal) - "PT281 Ultramarathon". The PT281® Ultramarathon is a foot race in a natural environment, covering forest trails, country lanes, dirt roads and asphalt. The route passes through the historic and natural landscape of Beira Baixa - Portugal and starts at Belmonte Castle and finishes in Proença-a-Nova. The total length of the route is 281 km, 6,733 D+, with a time limit of 66 hours for completion, in a non stop regime with the use of GPS and in semi self-sufficiency. It crosses 7 municipalities at an extremely hot time of year, with temperatures between 30º and 50º. https://horizontes.pt/en/pt281