Ata (may Allah have mercy on him) narrates from Ibn Abbas (may Allah be pleased with them both) that he was asked: Is the prayer to be shortened on a journey to Arafah? He said: No, but on a journey to Usfan, Ta'if and Jeddah it is shortened.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5399