yes, normally pavers are set on about 1.5" of sand. gravel can be used as top dressing for appearance and to help lock them into place.

Thanks. These appear to be poured in place concrete?

these are precast 24" x 24" pavers. you can get them from mutual materials or your local conc block/paver manufacturer

We used a compacted base of 5/8" minus crushed rock ( 4") to provide adequate support. The pavers can be leveled with a minimum of finer crushed rock (1/4" minus) or sand. We like to minimize the sand because in Seattle the rain tends to easily wash and we have found insects will disturb and change the grade.

Do you find the 1/4 minus is enough to hold the pavers without shifting? I have read some people use mortar mix underneath. I live in Portland and I bought Vancouver bay 24x24 and im about to start this project