Here's what it costs to ride the subway in 11 major US cities

• The BART, which runs through Oakland and San Francisco, can cost $10 for a single ride.
• Dallas and Houston - both with above ground light rails - have the cheapest trips on the list.
• New York's subway is one of the largest and oldest transit systems in the world and costs $2.75 per ride.

Public transportation isn't free.

New York City's subway system - the most-used metro rail system in the country - brings nearly two billion passengers to their destination annually. From work, to the mall, to the beach, urban dwellers and tourists rely on metros and light rails around the country.

Costs for these transit systems vary from city to city - sometimes depending on time of day or distance travelled.

We took a look at 11 cities and metro areas and compared the cost for a single, standard ride on the subway.