Wednesday's opening of the Rafah crossing, Gaza's main gateway to the outside world, is seen as a goodwill gesture ahead of the Muslim holy month of Ramadan, which starts next week.
Hamas, which rules the coastal strip, says more than 15,000 Gazans have applied to leave the coastal enclave, but only a few hundred can cross per day. Hamas says the crossing will remain open for four days.
Last month, Egypt reopened Rafah for two days.
Egypt has kept Rafah largely sealed since 2013, when ties with Hamas worsened after the ouster of Egypt's Islamist President Mohammed Morsi. Cairo accuses Hamas of supporting Islamic State militants in Egypt's restive Sinai Peninsula, which borders Gaza.
Want to enjoy 'Zen' reading - with no ads and just the article? Subscribe todaySubscribe now