Well, I think I can help you.

Go to https://spatialillusions.com/unitgenerator/ and you should see "Symbol Set" and it shows Land Unit.

Then click on the Land Unit and select Land Installations

In the upper left you see a large blue rectangle with a small black box on the top.

Go to Main Icon, click the drop down and you will see a lot of possibilities. Scroll down until you get to Airport

Then just explore the various drop downs.

Go to the bottom and you will see Show Additional Options and you will get some 'standard colors" but there is also a place on the right that you can select custom colors. In this case I indicated it is a Civil Airport, the name is MCO (Orlando International Airport, but it was original McCoy AFB), and it is fully capable.

Once you are satisfied with the symbol, you click png to save it to your computer. The icon will then be very large, but you can use a graphics program to change the size, and then save it with an appropriate name.

I suppose you could make a special symbol set that has all the symbols you want and then reduce the size in CC3+ rather than having a bunch of different sizes.

If you want to know more about the symbols, you can go here: https://www.jcs.mil/Portals/36/Documents/Doctrine/Other_Pubs/ms_2525d.pdf or you can search for Army Field Manual 1-02.2 Military Symbols. You should be able to download it from the Army Publication Site or other sites. IT will show examples for many symbols.

Tom's stuff is good, but I think the above is better, but since it is based on text, I think it is less flexible and sometimes does funny things. I used it a lot until I discovered these sites.

I'm sorry I failed to understand you were more interested in installation symbols rather than tactical symbols.

Well, you might look at this thread to follow my trepidations. It was quite a journey and the people on the board provided a lot of help. I frankly don't remember how I did a lot of things, but perhaps it will be helpful. I am still working on this game, after about 15 years, but the map work is mostly done.

I have made some changes since the thread terminated by hiding some roads and streams to simplify the map and reduce clutter. The game counters are larger, but the hexes are still 3km.

The map covers a region of 88km x 70km and the physical map itself is about 176cm x 140cm in 1:50000 scale. A grid square on the map is 2cm x 2cm, but because of the mapping convention, they sometimes become triangles to conform to the earth's surface.

If you are not using a topographic map, your work should be somewhat easier than mine was.

Of course, all it may do is confuse you. I don't have CC3+ on my computer at the moment and it has actually been a very long time since I made a map.

Wyvern is very generous in remarking upon my work. All my maps are made by using contour maps, usually at 1:100000 to 1:24000 scale and I mostly trace the contours and other features. My attempts at more generic maps look more like a 6 year old's scribbling. I was chastised mightily in third grade for my inability in penmanship, coloring, and staying inside the lines...

Having said that, I love drawing contour maps.

Jim was very, very talented in crafting maps. I was always impressed, regardless of whether or not it was a world or a starship or something else.

I was watching a Great Courses covering the dinosaur killer where they discussed the internal ring on earth as well on the moon. Otherwise I would not have thought to bring it up.