Handling a very large list of options for a user

I have an application that allows the users to select a location.

Currently I have 5 locations to pick from, but I'd like to expand this to use a master list containing about 100 options.

I also need to have the user's preference saved.

Currently, my working code works as follows:

Save Setting:

    My.Settings.SettingSearchLocationCAL = CInt(settingsRADlocationCAL.Checked)
    My.Settings.SettingSearchLocationMIS = CInt(settingsRADlocationMIS.Checked)
    My.Settings.SettingSearchLocationMON = CInt(settingsRADlocationMON.Checked)
    My.Settings.SettingSearchLocationLON = CInt(settingsRADlocationLON.Checked)
    My.Settings.SettingSearchLocationOTT = CInt(settingsRADlocationOTT.Checked)
    My.Settings.SettingSearchLocationTOR = CInt(settingsRADlocationTOR.Checked)

Determin which location was selected:

    If settingsRADlocationTOR.Checked = True Then
        LocationName = "ontario"
        LocationID = "1700272"
    ElseIf settingsRADlocationOTT.Checked = True Then
        LocationName = "ottawa"
        LocationID = "1700185"
    ElseIf settingsRADlocationMIS.Checked = True Then
        LocationName = "ontario"
        LocationID = "1700276"
    ElseIf settingsRADlocationLON.Checked = True Then
        LocationName = "london"
        LocationID = "1700214"
    ElseIf settingsRADlocationMON.Checked = True Then
        LocationName = "montreal"
        LocationID = "80002"
    ElseIf settingsRADlocationCAL.Checked = True Then
        LocationName = "calgary"
        LocationID = "1700199"
    End If

Currently, I'm using Radio Buttons for this, but I'm trying to figure out how I should allow the user to select their location. I've been experimenting with a File Menu, for the expandable menus features (Tree Arcitecture), seems to work ok for now.

My questuions are as follows:

Is there a better container I should be using? (User will select a Country, Province/State, and city. Ideally I'd like this all in 1 control, hence the file menu)

Is there a way I can import a txt file with the menu structure into the File Menu (or other container) as opposed to filling in each entry manually?

And.

How can I handle determining which option is selected on a list of over 100 entries? Would I need to continue having a .setting for each entry? or is there also a better way I can handle this?

Appreciate any help that can be provided. I hope what I've explained makes sense.

Thanks!

For the record, I decided to go with a File Menu, ComboBox simply did not meet my needs. Yes, it was an extensive amount of time to code it, but I'm much happier with the results.