Canal Walk
Extending from 11th and Senate at the north end to the NCAA headquarters at the south, the Indianapolis Canal Walk is a popular place for walking, biking, rollerblading, and peoplewatching. It's landscaped with flowers and fountains, and though it's pretty desolate during the winter, it can be worth visiting if there's ever a serious cold snap. In winter of 2000-2001, I worked at UPS on the graveyard shift and at Sprint PCS during the day. Impoverished, rather than pay for parking downtown, I'd park my car in a secret agent (read: free) spot on the west side of the canal on Vermont Street. That December it barely got above 15 degrees, and the floorboards of my car were frozen solid for the whole month. Crossing the Vermont Street footbridge across the canal, I paused on the mornings I wasn't running ridiculously late to marvel at the massive icicles that hung from the fountains. If you're ever in Indy in the dead of winter, I suggest you do the same.
Indy's canals were never used. Perennially a little behind the times, Indiana began constructing canals just before the railroads came through, rendering them obsolete before they were ever finished. The downtown canal was neglected until fairly recently.
At the south end of the canal, the path continues on to join Indy's surprisingly extensive greenway network. You can take greenways all the way from downtown to the Monon Trail in the Broad Ripple neighborhood. The Monon Trail, in turn, goes all the way up to 146th St.
Getting there:
There are numerous access points around the west side of downtown. I usually use the one at 11th and Senate because it's close to where I live, but if you're driving, you can usually find parking at Indiana & Senate, Vermont & West, New York & West (check the signs for times parking isn't allowed) and the White River State Park pay lot on Washington Street just west of West Street.
Costs:
Free, unless you want to rent a paddleboat, but I don't know how much that costs.
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