Well, well. Or actually, more likely a cistern, an underground storage vat. Sometimes the unexpected does emerge. In this case, it was in the form of an undocumented underground brick cistern that was discovered while crews excavated for laying underground utility lines. Archeologists came back to examine the find, but it seems likely at this time that the cistern probably pre-dates 1901. Utility lines were diverted around the brick cistern to avoid causing damage to it and to preserve it. It will be documented and reburied intact in case more thorough examination of it should be called for in the future. While the cistern likely bears no relation to Theodore Roosevelt's visit, it is a part of the Site's argheological heritage and should be protected. Perhaps new information in the future will suggest new importance for the cistern, or technological advances may provide the opportunity to learn things we cannot at this time. All part of what you deal with when you go digging on a national park site, and part of why we don't do it lightly.