You can add an option
tag on top of the others with no value and a prompt like this:
<select>
<option value="">Choose One</option>
<option value ="sydney">Sydney</option>
<option value ="melbourne">Melbourne</option>
<option value ="cromwell">Cromwell</option>
<option value ="queenstown">Queenstown</option>
</select>
Or leave it blank instead of saying Choose one if you want.