Y/D, if you like, is the transition from Mid Cape to Lower Cape. The southern or Sound side of Y/D is more touristy and feels a little like the Florida coast with its mini-golf courses, family eateries, and traffic. The Bay (northern) side is more quaint. Many travelers get off of Route 6 at Hyannis just before Y/D or keep on trucking through to Chatham or the Outer Cape.
Grumpy's (Dennis) - Breakfast destination
Scargo Tower - Kind of odd, but apparently a good view of Scargo Lake and Cape Cod Bay beyond. If you are in the area, may be worth a few minutes to stop by (55 cannot attest to the view as it was wicked foggy when we stopped). Scargo Hill Rd, South Dennis, MA 02660
Mayflower Beach - Nice looking beach with facilities. Because it is bayside, low tide goes way out which makes for fun beach walking through the tide pools. However, it's likely very crowded on beach days and it's a $30 parking fee in season (before 5:00 pm). 62 Horsefoot Path, Dennis, MA 02638
Corporation Beach - Similar to Mayflower above except for its horseshoe shape, with the same low tide and high pricetag. 250 Corporation Rd, Dennis, MA 02638
Smuggler's Beach
Sea Street Beach
Observatory (Thursday nights)
Sesuit Harbor Cafe
Devil's Purse
Candlepin at Ryan's Amusements
Pirate Museum