Here's a run-down.
Refer to this list:
http://wiki.project1999.com/Zones
*Antonica*
- All the ones listed "outdoors".
- Cities: all of them except parts/all of Neriak.
- Dungeons: Blackburrow, CT, Highpass Keep (not sure on this last one)
*Odus*
- Everything except The Hole and Erudin Palace (but the main Erudin zone is outdoors)
*Faydwer*
- Cities: Felwithe, Kelethin (duh)
- Every non-city zone except Kedge Keep
*Kunark*
- Everything listed under "Outdoors"
- Cabilis
- City of Mist, Karnor's Castle. Not sure about Veeshan's Peak.
*Planes*
- Fear, Hate, and Sky are all outdoors.