Get Map Directions on Google Maps
This basic HTML will redirect to google maps with directions from the input address to the Empire State Building. To have two addresses to input, just remove the type="hidden" tag from the Empire State Bldg input and remove the value.
<form action="https://maps.google.com/maps" method="get" target="_blank">
<label for="saddr">Enter your location</label>
<input type="text" name="saddr">
<input type="hidden" name="daddr" value="350 5th Ave New York, NY 10018 (Empire State Building)">
<input type="submit" value="Get directions">
</form>
Example: