But that hope has been sidetracked by disagreements over who should be allowed through, hours-long delays and Palestinian travellers' reports of being handcuffed and interrogated by Israeli soldiers.
Far fewer people than expected have crossed in both directions.
Restrictions negotiated by Israeli, Egyptian, Palestinian and international officials meant that only 50 people would be allowed to return to Gaza each day and 50 medical patients - along with two companions for each - would be allowed to leave.
But over the first four days of operations, just 36 Palestinians requiring medical care were allowed to leave for Egypt, plus 62 companions, according to United Nations data.
Palestinian officials say nearly 20,000 people in Gaza are seeking to leave for medical care that they say is not available in the war-shattered territory.
Amid confusion around the reopening, the Rafah crossing was closed Friday and Saturday.
The Rafah crossing is a lifeline for Gaza, providing the only link to the outside world not controlled by Israel. Israel seized it in May 2024, though traffic through the crossing was heavily restricted even before that.
Several women who managed to return to Gaza after its reopening recounted to The Associated Press harsh treatment by Israeli authorities and an Israeli-backed Palestinian armed group, Abu Shabab.
A European Union mission and Palestinian officials run the border crossing, and Israel has its screening facility some distance away.
Rana al-Louh, anxious to return two years after fleeing to Egypt with her wounded sister, said Israeli screeners asked multiple times why she wanted to go back to Gaza during questioning that lasted more than six hours. She said she was blindfolded and handcuffed, an allegation made by others.
"I told them I returned to Palestine because my husband and kids are there," al-Louh said.
Interrogators told her Gaza belonged to Israel and that "the war would return, that Hamas won't give up its weapons. I told him I didn't care, I wanted to return".
Asked about such reports, Israel's military replied that "no incidents of inappropriate conduct, mistreatment, apprehensions or confiscation of property by the Israeli security establishment are known".
The Shin Bet intelligence agency and COGAT, the Israeli military body that handles Palestinian civilian affairs and co-ordinates the crossings, did not respond to questions about the allegations.
UN human rights officials noted a "consistent pattern of ill-treatment, abuse and humiliation by Israeli military forces".
"After two years of utter devastation, being able to return to their families and what remains of their homes in safety and dignity is the bare minimum," Ajith Sunghay, the agency's human rights chief for the occupied Palestinian territories, said in a statement.
Officials who negotiated the Rafah reopening were clear that the early days of operation would be a pilot. If successful, the number of people crossing could increase.
Challenges quickly emerged. On the first day, Monday, Israeli officials said 71 patients and companions were approved to leave Gaza, with 46 Palestinians approved to enter.
Inside Gaza, however, organisers with the World Health Organisation were able to arrange transportation for only 12 people that day, so other patients stayed behind, according to a person briefed on the operations who spoke on condition of anonymity because they were not authorised to speak to the media.
Israeli officials insisted that no Palestinians would be allowed to enter Gaza until all the departures were complete.
Then they said that since only 12 people had left Gaza, only 12 could enter, leaving the rest to wait on the Egyptian side of the border overnight, according to the person briefed on the operations.
Crossings picked up on the second day, when 40 people were allowed to leave Gaza and 40 to enter.
But delays mounted as many returning travellers had more luggage than set out in the agreement reached by negotiators and items that were forbidden, including cigarettes and water and other liquids like perfume.
Each traveller is allowed to carry one mobile phone and a small amount of money if they submit a declaration 24 hours ahead of travel.
Each time a Palestinian was admitted to Egypt, Israeli authorities allowed one more into Gaza, drawing out the process.
