For example , the oases of Awjila , Ghadames and Kufra , in modern-day Libya , have at various times been vital to both North-South and East-West trade in the Sahara desert . For example , the oases of Awjila , Ghadames and Kufra , situated in modern-day Libya , have at various times been vital to both North-South and East-West trade in the Sahara .