Don't know if you are ever in Tampa, Florida but I was there recently and recommend it as a great place for cycling. This time of year, it's perfect weather - sunny as can be and the daily highs around 80 degrees (26 c). Plus, it's flat flat flat due to its location on the water, which also produces a nice gentle breeze to keep you cool
Bike rental in downtown Tampa is available from City Bikes (citybiketampa.com/(888) 484-2453) which offers Kona/KHS urban and mountain bikes for around $8.00 an hour with some nice road bikes renting around $10 an hour. Full day rates are around $30.00. Great people who know what they're doing run the shop and they're super friendly and nice. Plus you can find a coupon for 10% off in one of the downtown tourist map/attraction guides.
From City Rental on Cass Street, I rode south to the convention center, directly toward the water. Downtown Tampa is a calm place, so you won't have to be fearful of traffic. For an especially peaceful ride, take Franklin Street, just a block east of the City Bikes. Much of it is designated as car-free zones, and there is a great stretch that goes through a peaceful, shady mall area that runs a whole city block.
For a great ride, turn right/west at the Convention Center and cross the drawbridge over the Hillsborough River, which takes you directly to the path that follows Bayshore Boulevard. This is an awesome five-mile path for walkers, joggers and cyclists that follows the curve of the water all the way around. This is an uninterrupted path with no street crossings and numerous benches along the way, plus a convenience store at the far end for refueling.
I took the Bayside Boulevard path down and back, then followed the trolley line from the convention center over to Ybor City, a brick-street neighborhood of Tampa that'll make you think of New Orleans, just bursting with funky nightclubs, shops and restaurants. Lots of people sitting out in streetside cafes, sipping wine, etc. Originally developed as an area of cigar factories in the 1880s, there are lots of places in Ybor City to pick up anything from a light snack to full meal if you're looking for a place to eat.
From there, wrapping up my tourist adventure, it was an easy ride back east to City Bikes, not even a mile and a half. Two hours and 20 miles after I started I was back, and thankful for the opportunity to ride bikes in a lovely new area.
For even more riding and a different kind of area to explore, right on this route immediately at the end of the Bayside path at the convention center are Davis Island and Harbour Island. Davis is the better of the two for riding and interesting things to see, as Harbour Island is basically an enclave of private communities that you may or may not be able to access plus a handful of shops and restaurants. Davis Island, on the other hand, has an array of public residential streets, a main drag with a number of great places to check out, and a long looping route (Davis Boulevard) that takes you the length of the island, including right past the tiny airport at the tip.