You are looking for a traditional cache that is big enough to host several TBs. Many muggles around, especially during the school year. Congrats to toolrep1 on the FTF!
From Wikipedia:
The Midway Plaisance, known locally as the Midway, is a Chicago public park on the South Side of Chicago, Illinois. It is one mile long by 220 yards wide and extends along 59th and 60th streets, joining Washington Park at its west end and Jackson Park at its east end. It divides the Hyde Park community area to the north from the Woodlawn community area to the south, 6 miles (10 km) south of the downtown "Loop", near Lake Michigan. Today, the Midway runs through the southern portion of the University of Chicago campus, with university and related buildings fronting it on both sides.
It early came to prominence when it hosted amusements at the World's Columbian Exposition in 1893, lending the name "Midway" to areas at county and state fairs with sideshows. Laid out with long vistas and avenues of trees at the start of the 20th century, the Midway in part followed the vision of Frederick Law Olmsted, one of the creators of New York City's famous Central Park, but without his design of creating a Venetian canal linking the lagoon systems of Jackson and Washington parks. Instead, the Midway is landscaped with a fosse or dry ditch where the canal would have been.
Later designers and artists added (or sought to add) their vision to the Midway. A pet project of the University of Chicago and almost a part of its campus, it has remained essentially a green area.