It takes time to get into Gaza.

There are two points of entry into the besieged strip: Rafah in the south and Erez in the north. With Rafah frequently closed, Erez is often the only way in for visitors, although it remains closed to many Palestinians. This is why some refer to Gaza as the world's largest open-air prison.

After obtaining approval from a lone guard outside to enter the Erez checkpoint, visitors move into a cavernous border-control warehouse, where another guard checks and stamps passports. Then it's on to a maze-like passageway that - after two subsequent turnstiles, which seal off access to the way back - spits people out at the entrance to a long, winding, covered walkway.

What grabs one's attention immediately on the long walk from Erez into Gaza is Israel's separation wall, an imposing concrete barrier that successfully blocks all view of what's on the other side. The feeling of separation, of being cut off from the rest of the world, is absolute.

The walkway into Gaza stretches into the horizon. A couple of men have developed something of a business carting passengers and their luggage from one end to the other on motorized carts. As the carts move closer to Gaza, the only view comes through the metal grating on the sides of the walkway. There is a sense of being drawn into a trap, into a prison.

And then, finally, the passageway ends. At the other end of the Erez crossing, taxis wait in the dusty mid-afternoon sunshine to bring visitors into Gaza and residents back home.

Erez is not a viable option for many Palestinians, who can only cross at Rafah upon the whims of Egypt, which frequently shuts access.

It takes time to get into Gaza. But for many Palestinians, it takes much, much longer to get out.

Follow Megan O'Toole on Twitter: @megan_otoole