Passwall

A passage appears at a point of your choice that you can see on a wooden, plaster, or stone surface (such as a wall, a ceiling, or a floor) within range, and lasts for the duration. You choose the opening's dimensions: up to 5 feet wide, 8 feet tall, and 20 feet deep. The passage creates no instability in a structure surrounding it. When the opening disappears, any creatures or objects still in the passage created by the spell are safely ejected to an unoccupied space nearest to the surface on which you cast the spell.

Passwall creates a passage through wooden, plaster, or stone walls, but not through metal or other harder materials. The passage is up to 10 feet deep plus an additional 10 feet deep per three caster levels above 9th (20 feet at 12th, 30 feet deep at 15th, 40 feet deep at 18th). If the wall’s thickness is more than the depth of the passage created, then a single passwall simply makes a niche or short tunnel. Several passwall spells can then form a continuing passage to breach very thick walls. When passwall ends (due to duration, dispel magic, or caster's choice), creatures within the passage are ejected out the nearest exit.