Hundreds of Jordanian Hajj pilgrims on Wednesday boarded air-conditioned buses bound for Makkah, officials said, marking the start of a 1,900km road journey to one of the most important events in Islam's religious calendar. Official data show that out of Jordan’s 8,000 pilgrim quota, two thirds will be travelling by bus over the next two days, while most of the rest will travel by plane next week. As usual, a significant proportion of the pilgrims this year are elderly, with 1,700 born in 1946 or earlier. “Hajj is not easy. It requires co-operation from everyone to make it succeed,” said Jordanian Religious Affairs Minister Mohammad Al Khalaileh. A round-trip plane ticket from Amman to Jeddah during Hajj costs almost $1,000 – twice as much as the bus fare from Amman to Makkah – making overland travel the most popular option for Hajj travel from Jordan. Per capita income in the kingdom was $4,100 last year, according to the World Bank. Pilgrims from all over the kingdom have been have been streaming to an inspection centre in the Jiza desert area south of Amman where their buses undergo a technical check before heading to another assembly point in the city of Maan. From there, the buses set out for the Al Mudawara border crossing with Saudi Arabia in groups of 10, to prevent congestion. The first pilgrims were expected to cross into Saudi Arabia by Wednesday evening. Abu Khaled, head of a Hajj travel agency in Jordan, said the last buses would leave on Friday. Every Jordanian planning to perform Hajj must register with a Hajj agency, which will give pilgrims orientation sessions before they leave for Makkah. The agencies assign two staff members to accompany every 35 pilgrims. This year, 2.6 million people from around the world are expected to perform Hajj.