We took the Viking River Wheel to slowly walk up the Danube River, the river is calm and clear, the blue sky and white clouds on both sides of the green mountains. On the fourth day of the Viking River tour, we entered the most beautiful scenery on the Danube River, the Wahao Valley. Beautiful towns built by the water are in sight. The valley of the vae is the Danube valley, which is more than 30 kilometers long between Merk and Crems. The countryside is picturesque, the monastery is solemn, the castle is romantic and the grapes are lush in the mountains, which make up the famous scenery of the vae valley. In 2011, the Valley was included in the United Nations World Heritage List for its rich natural resources and long human history. The Viking wheels enjoy the Valley, the scenery is intoxicating in the green mountains and green waters.