Who’s buried in Grant’s tomb? You can find out for yourself when you visit the General Grant National Memorial in New York City. Along with the mausoleum, there’s also a museum you can visit.
Riverside Drive and West 122nd Street, New York City
https://www.nps.gov/gegr/index.htm
We have three posts about Grant’s Tomb: Part 1, Part 2 and Part 3.
Nerd Trips ABCs:
Admission fee: No
Bathrooms: Across the street in the Visitors Center

The playing cards even had two “jokers,” two men who won the popular vote but lost the presidential election – Al Gore (2000) and Samuel Tilden (1876)
Concessions/food: Not on site, but it’s New York City, you’ll find something nearby
Cars/getting there: We took the subway, then walked a few blocks. We took a taxi home. Website has links about public transportation. Limited street parking.
Coffee cups (aka souvenirs): Along with the usual postcards, I picked up presidential playing cards!