Originally Posted by
Fly_IAD
If you've never been to Israel than after or before your conference spend time based in Jerusalem. I'd skip Haifa all together and since your not driving there is really very little point to trying to explore the North and figuring out public buses, your trip is simply too short for that (again, given your not driving). From Jerusalem you can get buses to the Dead Sea/Masada and all around the area if hiking is your thing (you mention trail running). Jerusalem is just a must.
I totally agree that Jerusalem is the most important.
Masada + Dead Sea by public transportation can be done if you're a savvy independent traveler, but it's not the easiest thing in the world. Buses are infrequent and you need to time it well. Plus, the buses don't stop exactly where you need them to; for example, the public bus drops you off on a random road about 10 minutes from Masada. The good thing is that Israelis love giving people directions (not necessarily correct) and will help you. I generally hate organized tours, but OP *might* want to consider an organized day trip for Masada + the Dead sea.
Without a car, OP won't have time for hiking around that area.