To circumvent the blockade, Palestinians built hundreds of underground tunnels crisscrossing the Gaza-Egypt border to bring in scarce consumer goods, as well as weapons. But after Israel started letting in more consumer goods a year ago, tunnels were freed up to bring in materials that remained severely restricted — such as raw construction materials.

The prices of raw materials dropped, sparking a flurry of construction.

Some 150 of Gaza’s estimated 700 tunnels are solely used for raw materials, said two tunnel traders who requested anonymity because they dodge Hamas taxes. Some 120 tons of raw materials are typically hauled daily through a single tunnel, they said. The rush of new building materials pushed down concrete from a blockade high of $900 a ton to $157. Gravel was $990, now it’s $28.

Restrictions on exports and imports make some construction projects, including factories, unfeasible. Investors are instead undertaking projects that target domestic consumers, such as the al-Andulusia mall that opened in July.

The $4 million, three-story shopping center, is a humble operation by global standards. It has a large supermarket and an assortment of clothing and shoe shops. The third floor — a future cinema — hasn’t opened yet.

For many Gazans, whose lives have stalled in fighting and the blockade, the novelty is apparent.

On a recent visit to the al-Andalusia mall, two women clutched the escalator’s rubber grip, giggling and shrieking as they rode up to the second floor. Another woman stared at the escalator in fright, unsure how to get on.