Size wise the second largest state in the United States of America is Texas. It also happens to be the second most populous state right after California. It is also called the Lone Star State and is abbreviated as US TX, Tex or just TX. Its motto is friendship and in fact the word Texas itself means allies or friends. Texas as a state has number of important cities and towns that are worth visiting. Let us get started with Houston. Houston has its own well known museums - Museum of Natural Science