Located on the right side of the road from the beach to the memorial house, 175m from the sea (high water level), a stele was erected in the middle of the sweet potato field where Uncle Uncle dug up to see the tubers.
The stele was carved on fine-grained stone, 1.2m high, 0.8m wide, covered with washed stones. The whole work was 2.4m high and 1.5m wide, placed on a pedestal of 3.4m long and 2.0m wide.
The content of the stele says, "On this field, President Ho Chi Minh dug up sweet potatoes and praised their good quality during his visit to Co To Island on May 9, 1961". Opposite to Doc Khoai stele is an artificial lotus pond of 43m long and 37m wide, with an area of 1,591m2, about 8m from the main road. The lotus variety planted in the pond was brought here from Uncle Ho's hometown by the youth union members of Co To district.
Previously, this area was the sweet potato field of the people on the island, located by the road from the beach to the Memorial house (the path Uncle Ho went from the place where the plane landed to the headquarters of the Co To Commune Administrative Committee). When passing the field, Uncle Ho wanted to see the yield and quality of the sweet potato varieties planted on the island, so Mr. Hoang Chinh - Secretary of the Hai Ninh Provincial Party Committee dug up a bunch of sweet potatoes for Uncle Ho to see. Today, Doc Khoai (Sweet potato slope) area is planned to be located in the relic site with a stele marking the event. The stele was erected on the right side of the road from the outside, in the middle of the sweet potato field where Uncle Ho dug up sweet potatoes, located about 160m from the sea at high water level. The stele is built on a three-level pedestal. It has a rectangular shape, its forehead is curved, and its center is decorated with a five-pointed star. The stele is made of fine-grained green stone, 1.2m high, 0.8m wide, placed on a three-level pedestal of 3.4m long and 2m wide. The forehead of the stele is decorated with cloud pattern, in the middle is an embossed five-pointed star surrounded by a circle. The edge is decorated with the lotus flower pattern. The two sides of the stele are made flat. Its front is engraved with the words: "During his visit to Co To island on May 9, 1961, President Ho Chi Minh stopped at this field to see the sweet potato varieties planted on the island. Seeing a lot of tubers, he praised and advised locals to develop this crop". Currently, after the stele, there is still a part of the area planted with sweet potatoes.
Today, the three relics including the Monument of President Ho Chi Minh, the Temple of President Ho Chi Minh and Doc Khoai are planned to be located in the same campus. The main area is where the helicopter carrying Uncle Ho landed in the warm welcome of all residents on the morning of May 9, 1961. Up to now, the campus has undergone many renovations and expansions. Currently, the historical relic of President Ho Chi Minh memorial site on Co To island has been invested to embellish and expand the area behind the Temple, connecting with the Memorial House with a total expanded area of up to over 62,000m2, surrounded by the walls that were built of red bricks, added pillars and decorated with lemon flower ceramic bricks. Inside the campus, in addition to the three relic sites, there are gardens, ornamental plants, pine park, fish pond, and rockeries to create a landscape environment for the relic. On the right side of the road is Co To Buddhist Pine Park, which is designed in harmony with trees, green fences and some shady ancient trees. At the two corners behind are large fruit trees along with clusters of paperflower (bougainvillea) blooming in summer, creating many colorful emotions for tourists.