With a possibly smaller size sign, adding a QR code could allow those reading the sign to use their smartphone to get more information than can be displayed on the sign. So as a demonstration, here are two sample codes:
WW&F Home page:
The QR code above takes one directly to the WW&F home page, so is useful, but the home page is somewhat generic for a sign located at Hwy #218. But QR codes are not limited to just a homepage, there could be a QR code on the Hwy #218 sign that redirects to a specific page within the WW&F site. As an example of this concept, I prepared a second QR code below that redirects directly to the WW&F "Volunteering" page:
WW&F "Volunteering" page:
Those QR codes are 'live', and work fine with my Android phone, so you could try scanning them with your phone and they should take you to their respective web page.
I used the "Volunteering" page because is was handy, but there
could be a page more specific to the Mountain Extension, or if desired on a sign at a different location, any other WW&F webpage.