My Reminders is "on" and I can enter what I want, but it won't let me set the"when I arrive" location. The address of the location I want shows with a red pin and looks to be highlighted in gray but I can't get the "when I arrive" to be the choice (darker blue). iOS6 was easy to set the location but not so in iOS7.
I was able to get it to work by enabling Reminders in iCloud. It still doesn't show up in Location Services but I can get into it now from the app. Found some info here that helped though it's not iOS 7 specific: https://discussions.apple.com/thread/3374979?start=0&tstart=0
-enabled reminders in iCloud under Mail, Contacts, Calendars
-started a new reminder and chose "remind me at location"
-Reminders app asked if it could use my location
-choose yes/ok
-Reminders shows up under Location Services
Reminders is turned on everywhere I can find it. The issue is that I cannot find a way to access my contacts to choose the location I want to set for "when I arrive". Sorry I didn't make that clear early on. :-(. Is there a setting I have missed to enable using my Contacts in Reminders? Surely Apple didn't take that away.
Settings > Reminders > Default List > iCloud
I had my reminders default list associated with "Tasks" from a microsoft exchange server account that stopped working in late 2012. I needed to select iCloud and then it worked. Best of luck!
Settings -> Reminders -> Default List -> should be set as your iCloud account (not an exchange account).
If your iCloud account isn't present, go to Settings -> iCloud -> enable Reminders