Where does the pilgrim pray Maghrib and Isha: shortened or combined-shortened as stated in the Sunnah?

It is legislated for the pilgrim to combine the Maghrib and 'Isha prayers and to shorten the 'Isha prayer only in Muzdalifah. The Sunnah is not to pray Maghrib until one reaches Muzdalifah, and then to combine the two prayers, due to the action of the Prophet (peace be upon him). There should be a separate iqamah for each prayer, although it is permissible to suffice with one iqamah for both.