I like to add non-combat goals to my encounters.
Some merely add to the difficulty, some provide a non-combat resolution to the situation. If players get to this spot and get/pull/steal/kill/break/unlock/retrieve/save the __________ (fill in blank according to your story) then x will happen either disarming the situation or making the victory unavoidable. Or as opposed to resolving the situation, getting to Y stops it from getting even worse. If Y is ignored then the situation becomes increasingly difficult. At you leisure add x elements or y elements, and when you really want chaos, add both at once.
Elements like this while a battle is raging give the PCs a chance to use skills instead of attack powers to resolve situations. Now that the characters have a very concrete motivation to get to that place, let your imagine run wild as you come up with fun obstacles that impede them from reaching that place without some effort.
i think building terrain upwards as well as outwards is a fun element. Also up there is a good place to put the __________ or the Y to make the PCs get up there, climing, leaping, teleporting til they reach their objective.