Da Nang is hiding 25 pieces.

Plan for a half day, around 4 hours, at your own pace: about 9 km on foot plus time to solve, look around and eat. Progress saves, so you can stop for coffee or lunch, or split it over two days.

A phone with a camera, mobile data and location turned on. It runs in the browser on any recent iPhone or Android, so there is nothing to install. Bring water, sun cream and a charged battery.

The route is flat city walking on pavements and riverside paths, with one long bridge crossing on foot. A few stops sit in temple or museum grounds that may have steps. We have not checked every stop for wheelchair access yet, so if that matters to you, ask us before you play.

Every stop is in a public place you can reach on foot, and you photograph from where anyone can stand. Da Nang traffic is busy: cross at crossings, walk at a steady pace, and look up from your phone at the kerb. We recommend playing in daylight.

Midday can be very hot, so mornings and late afternoons are best. The rainy season runs roughly from September to December. Your code lasts a year until you finish, so you can wait for a dry day.

You never get stuck. Skip to the next clue whenever you like. If all five clues miss, the game shows you where the object is, and walking within 25 m of it wins the piece. You just score a six for that stop.

The game lets you move on. A patchy location fix or a photo the checker cannot read never ends your walk: you can carry on to the next stop, and that piece shows as unlocked with help on your card.

Yes. A group can share one phone on one code, or link several phones so a find on one unlocks for everyone. Each linked player gets their own puzzle and treat at the end. Linked codes can also play Competitive as one team, with one entry on the leaderboard, or race each other in VS.

No. Every code can play Solo, Crew, Competitive or VS, and testers pay nothing at all. Linked codes can play both: Competitive as one team, and VS against anyone, crewmates included.

Competitive and VS give you three, each once per walk. A crew playing as a team shares one set. Distance shows live metres to the spot and Compass shows the arrow to your search area, both until you solve that stop. Free skip shows the next clue at once, with no wait and no extra move.

Yes, as long as they have their own Jigwalk code. There is no matchmaking: send the 6-character match code however you like, they choose Competitive and Join VS, and you both press Ready. A match that never starts closes after 12 hours.

Finished Competitive and VS walks in Da Nang, on two boards each season. Best score ranks the fewest moves first, with the faster time breaking a tie. Fastest ranks the quickest finish first, with fewer moves breaking a tie. The clock starts with your first photo in the first search area; a VS match runs from its shared start. If two walks are still level after that, the one with fewer lifelines goes first. Each line shows a nickname, or a team name with a crew badge, then moves, time and lifelines used. Every walk is checked before it posts, and a walk that switches out of Competitive never posts.

Not to play: your game code is all you type in. Free tester codes are claimed with an account, one claim per account. The leaderboard only ever shows the nickname you choose at the finish.

English, for now.

Until 7 days after you finish, so you have time to collect your puzzle. If you have not finished, the code stays open for a year from when you get it.

Not for testers. The launch price will be $50 for the first player and $20 for each extra player on a linked code. Tester codes are free while places last.