Receiving a parking ticket in the city of trees isn't usually expensive, but they can add up. If thousands of them go unpaid, it can add up to almost one million dollars.

According to the city of Boise, they're sitting on just under $1,000,000 in unpaid parking tickets. To be exact, since 2009, there are 47,484  unpaid tickets. They add up to $953,000 owed to the city.

The most costly unpaid ticket? $690.

Luckily, the new "Parkmobile" parking app is already cutting down on parking tickets issued in Boise, especially downtown.