On Campus Tunnels

One of the best ways to identify a new and booming city is cluttered infrastructure. Cables, pipes, and power lines are particularly infamous for clumping like spiderwebs in a fast-growing city. The only alternative to putting these cables above the ground on poles is...to put them under the ground in holes. Instead of just burying a small pipe, worker-accessible tunnels are usually built around them, to allow repairs and expansion. Gutters are another popular thing to bury. Nobody wants a river rushing down the sidewalk across their whole city, so they put in pipes to carry water; pipes that have to be big enough to remove rainwater even when several inches per hour fall.

So what looks like solid ground often isn't, especially in a place with established infrastructure; and nearly always when you see no other infrastructure. Look around. Are there large buildings with no power lines going to them? Then they're fed by buried cable. If there are enough large buildings around, it's cheaper to make a tunnel than to constantly dig up cable for repairs and upgrades. University campuses are well-known for their ubiquitous 'steam tunnels,' and the downtown urban areas have them as well. I'll borrow a picture fromULiveAndYouBurn's site. Steam tunnels generally look a lot like this:

That is, concrete with a lot of pipes and a little bit of room to walk along it. These days many are secured pretty closely; there is legitimate fear of someone stupid getting in and getting hurt, and paranoia about terrorists sabotaging infrastructure. However, with a little bit of caution and knowledge of the local system, you gain the opportunity to find some really neat places that very few people know about:

Off the Beaten Path, taking a break after class.