Locals have a chance to challenge their brains through a citywide scavenger hunt that kicked off last week.

The city of Palo Alto has teamed up with local organization Solving Fun for the free four-week event, in which one puzzle will be released each week. For weeks two through four, the puzzle will be available on Thursdays at noon.

Here's how it works: Participants can download and print the puzzles at solvingfun.com/paloalto, or pick up a printed set at the Mitchell Park or Lucie Stern community centers. Every challenge takes players to a different part of the city where they'll search for a sign with a series of bold letters. Organizers note that the signs won't be hidden or buried and will be placed on public property. "You will not need to damage anything to find them," directions posted on Solving Fun's website state.

Once players write down the letters, they can put them together for that week's final answer, which can be entered through a Google Form on Solving Fun's website or written on the printed form and dropped off at any city community center.

Players can enter into a drawing each week for their shot at prizes. Those who complete all four weeks of puzzles can figure out the final location based on all the answers from the previous weeks and a last set of puzzles. The ultimate drawing will be for a grand prize of Palo Alto goods, according to Solving Fun's website. For more information, visit solvingfun.com/paloalto.