The force field exerted a membranous resistance as Marie went past it. As her face passed the thin film, her sight warped and grew brighter by a significant order of magnitude. It was a jarring change in visuals, as from outside the field all she saw was a cavern shrouded in darkness.
A few more steps in and Marie was forced to witness a sight that made her question her sense and understanding of scale and spatial positioning.
Imagine a mountain, and then hollow it out from within. "Is it me or is the interior far bigger than the exterior of the mountain? This has to be some sort of optical illusion, you cannot just hollow out a mountain like this and not expect the damn thing to collapse unto itself."
"The interior is, as you predicted, enchanted to increase its spatial capacity," Mage Maddi responded with a proud smirk on her lips. "It is the result of the hard work of our previous Sect Leader."