Hold Portal

(Player's Handbook v.3.5, page 241, DnD 3.5)

Abjuration

Level: ; Sorcerer/Wizard 1; Sha'ir 1; Savant 1; Urban Druid 1
Components: V
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Target: One portal, up to 20 sq. ft./level
Duration: 1 min./level (D)
Saving Throw: None
Spell Resistance: No

This spell magically holds shut a door, gate, window, or shutter of wood, metal, or stone.
The magic affects the portal just as if it were securely closed and normally locked.
A knock spell or a successful dispel magic spell can negate a hold portal spell.
For a portal affected by this spell, add 5 to the normal DC for forcing open the portal.