RAFAH, Gaza Strip -- It was once home to an estimated 1.4 million people, over half of the population of Gaza, many of them displaced from the north of the enclave after Israel launched its military offensive following Hamas' Oct. 7 terror attacks.

Today, Rafah is uninhabitable, its buildings crumbled and blackened. Mounds of concrete and bent metal are all that remain. The destruction is absolute.

When NBC News was invited into Gaza's southernmost city by the Israel Defense Forces on Friday, there were no civilians to be seen, just a few cats. Sporadic gunfire and the odd drone overhead punctuated the eery silence.

For more on this story watch "NBC Nightly News with Lester Holt" tonight at 6:30 p.m. ET/5:30 p.m. CT.

The Israeli military says the reason for so much destruction is that all of Rafah is honeycombed with Hamas tunnels, some of which sit on top of each other and some are more than 160 feet deep. The drills they use to find open spaces beneath the earth's surface lie several feet apart.

Calling the destruction a "tragedy," IDF spokesperson Rear Adm. Daniel Hagari said Hamas created a "very, very sophisticated" tunnel system underneath the city and the military has tried to demolish it "with minimum damage to the city."

He added that some of the buildings had been booby-trapped with explosives and some of the destruction had been caused in battles with Hamas.

In the Tal Al Sultan neighborhood lies the tunnel where the bodies of six hostages including American Hersh Goldberg-Polin, 23, were found late last month.

The IDF made some videos of the structure public on Tuesday. They said it showed how the tunnel was dug below a child's bedroom that had paintings of Mickey Mouse and Snow White on the walls.