What type of gravel should I use?

One of the best gravels to use for building roads on top of native soil is 2 inch crushed, or "railroad ballast". Applied no less than four inches thick it makes an excellent base which holds itself together over most areas. After this is applied and properly compacted, a layer of 5/8 minus (minus means fine particles are included to form a tight, stay put layer) crushed rock, no less than two inches thick, will top dress it nicely for horses and humans alike. Many people make the mistake of just putting down the smaller rock over a muddy or wet area, but that usually doesn't hold up very long. That's what the bigger rock is for, to act as a base to "ride" over any soft spots and to prevent soft spots from appearing later after trucks, cars and horses have been back and forth over it.

Access roads...

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