Using Garmin Etrex Abroad?

I've got a few weeks hiking in Montenegro planned this summer and want to take my GPS. However, I'm not sure how the grid refs will relate to the maps I will have. In the Pyrenees a few years back, we couldn't work it out either - it was giving us grid refs, but they didn't match our Spanish maps.

 Does anyone know if I need to load on any other topography for this to work? I basically want to know where I am in the Montenegran mountains by grid reference.

 Any tips much appreciated!

 Thanks - Paul

Okay - I need to get the maps ordered then!

 So, when you say the grid refs will be given by the GPS in lat/long, will that relate directly to the map, or will they need converting?

Thr grid refs may not be lat/long.

A lot of European maps use WGS84 survey datum in conjunction with the UTM/UPS grid. And that's a standard combination that your Garmin setup allows and then displays you a grid ref that you use similarly to an OS one.

However, you can't be sure if this is the case until you get the details for the specific map you intend to use.