This is not really a Civil 3D specific tip and this command has been around for several releases, so I thought it needed to be brought back to surface for your consideration.
The ability to link drawing objects and blocks to a website is something that is sort of intriguing to me. I happened upon it several years ago, but probably like everyone else, they said “wow, cool” and then promptly forgot about it.
The key to getting this to work is in the properties. I have a very simple block of a manhole shown here. When I click on the block and go over to the properties, click on the Extended Data.
Click on the Hyperlink and enter the website. For this example, I am linking the block with a local mahole manufacturer.
Now back in your drawing, if you hover over the block, you will see a new glyph indicating that it is hyperlinked.
And if you CTRL + click on the block, it will open your browser to the webpage.
Pretty cool and simple. I’d like to hear your comments whether you use this feature or not.