What do you think about this? This was at the visitor's center at Burlington Northern RailRoad.
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BTW, here is a selected part of 30.05:
PC §30.05. CRIMINAL TRESPASS. (a) A person commits an offense
if he enters or remains on or in property, including an aircraft or other
vehicle, of another without effective consent or he enters or remains in
a building of another without effective consent and he:
(1) had notice that the entry was forbidden; or
(2) received notice to depart but failed to do so....
(f) It is a defense to prosecution under this section that:
(1) the basis on which entry on the property or land or in the
building was forbidden is that entry with a handgun was forbidden; and
(2) the person was carrying a concealed handgun and a license
issued under Subchapter H, Chapter 411, Government Code, to carry
a concealed handgun of the same category the person was carrying.