Have you noticed yourself feeling joy lately? Is your mood starting to pick up? If so, it's likely you need a good blow to your sunshine, and the Dallas Underground exists to serve you. This late 20th century tunnel system provides a functional link between some of Dallas' largest office buildings, and contains central areas housing unexpectedly diverse food courts and newsstands. Access it via the unsettlingly concealed stairways labeled "to concourse" on the first floor of buildings such as the Bank of America Plaza or Hotel Indigo. You'll quickly realize it's not a place you want to enjoy for too long. Its fluorescent-lit concrete corridors, reminiscent of a Soviet-era bomb shelter, are always a-bustle with powerwalking office workers and midday snack hunters. It's well worth a visit as a sort of cultural relic, even if it comes at the expense of your happiness.