A couple people in this thread have recommended a SPOT or other SEND (Satellite-enabled notification device) but these are overkill for your purposes because your tour is going through urban and suburban areas. Also SENDs use private sat networks like Iridium which means you need to pay a fee to use them.
Originally Posted by
Bassmanbob
I was looking at the Garmin 820 anyway. Will this do it? Do I need a website for the GPS to send the information or is there an app she can download on her iPhone?
Yes. The 820 comes with an app for your phone; you tell the app you want to do a "live tracking" session, and give it your wife's email address. It will send her a link to a map with your current location (and heart rate and speed). If you lose reception for a moment, it will pick up when you get it back, and it will show the route you took while you didn't have coverage. I use this all the time with my Fenix 3.