Sylios Corp. (fka UNGS)

[rmuncast]

For historical prices, I usually just look at the table (in the link I provided). On the same site you can check out the interactive chart, and when you hover your mouse over the chart, it will show you the open/close/high/low/vol for that day in the top right.

I'm sure there are also some sites where you can choose on the charts whether it shows closing price, or high of day, or low of day, or whatever.