Where is U.S. Grant buried?

In Grant's Tomb, New York City.

Grant's Tomb, now formally known as General Grant National Memorial, is the final resting place of Ulysses S. Grant, the 18th President of the United States, and his wife, Julia Dent Grant. Completed in 1897, the tomb is located in Riverside Park in the Morningside Heights neighborhood of Upper Manhattan in New York City, across the street from the monumental Riverside Church. It was placed under the management of the National Park Service in 1958.