That's for sure. Both see my full text on the inn keeper law. Also if you go to COMAR on the rest stops, it just says display or discharge is prohibited.
Of course. if you combine no displaying or discharging of firearms at a rest stop, with the blanket "no open or concealed carrying of firearms" in a government building means you should lockup your gun at a rest stop unless you are just pumping gas. I am not sure the status of the few gas stations as Maryland rest stops (if the building it privately or publicly owned) and you'd be outdoors, so fine so long as the handgun was concealed. However, all other facilities at Maryland rest stops are state property, therefore you cannot carry a firearm into them.
I disagree a rest stop is a part of a highway and I will continue to carry at those locations.
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