Why did the three natural bridges of Wulong become a geological legend of Wulong, hiding an unknown code in the karst landform?

Chongqing Wulong Tiansheng Three Bridges Day Tour Guide Preliminary preparation 1. Documents: Prepare your mainland China ID card for ticket purchase and inspection at the scenic spot. 2. Clothing: Check the weather in advance and prepare clothes according to the season. To prevent heatstroke in summer, bring light and breathable clothes 🎽 and sunscreen products; to prevent cold in winter, wear thick down jackets, scarves, and gloves. 3. Items: Bring a power bank to ensure your phone is fully charged; bring comfortable sports shoes for easy walking; bring snacks 🍟🍿🍥 and water 🥛🍵☕🥤 to replenish your energy. Transportation 1. Public transportation: Take a bus to Wulong Tourist Center at Chongqing Sikmli Transportation Hub. The journey takes about 2 hours and the fare is about 40 yuan. After arrival, transfer to the scenic area transfer bus to Tiansheng Three Bridges. 2. Join a tour group: There are many one-day tour groups in Chongqing city. Booking on a regular platform includes round-trip transportation and tickets, saving you time and effort. 3. Self-driving: Starting from downtown Chongqing, drive via the Baomao Expressway, the journey takes about 1.5 hours. There is a parking lot in the scenic area. Ticket Information Book your tickets online in advance. Adult tickets are around RMB 115 (including tickets and sightseeing bus). Students can enjoy a half-price discount with valid ID. Tour route 1. Tianlong Bridge: Take the sightseeing elevator down from the entrance, and you will see the Tianlong Bridge. The bridge is tall and has a large span, which is magnificent. Passing through the bridge hole, you can see Tianfu Official Posthouse, where the movie "Curse of the Golden Flower" was filmed. The ancient buildings blend with the green mountains and waters, and you can take photos as a souvenir. 2. Qinglong Bridge: Walk along the trail to Qinglong Bridge, which is the highest of the three natural bridges. There are often clouds and mist after the rain, and under the sunshine, it looks like a blue dragon flying. Standing in a specific position, you can capture the beautiful picture of the bridge, sky and valley. 3. Black Dragon Bridge🐲: Finally we came to the Black Dragon Bridge. The light in the bridge hole was dim, adding to the mysterious atmosphere. There are many clear springs flowing out from the cave wall, such as the Mist Spring and the Pearl Spring, forming a unique landscape. Be careful of slippery feet when visiting. Food Recommendations 1. Yankou Dried Beans🍢: A specialty of Wulong, with a delicate and chewy taste, a variety of flavors to choose from, and can be purchased in the scenic area store. 2. Bowls of mutton 🐑: Made from local goat meat 🥩, stewed until tasty, served with rice 🍚, fresh and warming. You can taste it in restaurants near the scenic area. Note x 1. There are many stairs in the scenic area. Please pay attention to safety and avoid running when visiting. 2. There are many tourists during the peak season, so plan your trip in advance, book tickets and transportation, and travel during off-peak hours.