There are literally thousands of beds on MDI , which helps to keep prices low even in the summer. Some of the cheapest are at Robbins Motel (Rte. 3, Bar Harbor, 207/288-4659, www.acadia.net/robbins , May–mid-Oct., $58), which features the rates of yesteryear and rooms to match. Amenities, such as they are, include cable TV, a pool, and free Wi-Fi. Reserve ahead for the best rates.
In the center of Southwest Harbor, Penury Hall (374 Main St., Southwest Harbor, 207/244-7102, www.penuryhall.com , $130) is a bed-and-breakfast located on the former site of Fort Prentice—signified by the replica of the cannon out front. The bright-green living room is full of puzzles, games, and a cat to keep guests occupied, while rooms are nautically themed and snug. Other perks include a canoe for borrowing and a sauna for relaxing after a hard day on the trails.
Inhabiting one of the few surviving summer cottages in Bar Harbor , Mira Monte Inn (69 Mt. Desert St., Bar Harbor, 800/553-5109, www.miramonte.com , $170–245) captures an Old World feeling without any pretension. The rooms are full of little luxuries, like a wood stove, whirlpool tub, and warm towel racks, while an amazing breakfast spread ensures you’ll have the energy for your outdoor pursuits. On that front, owner Marian Burns is one of the first bed-and-breakfast operators in town, and is full of advice on secret spots in the park.
Gardens full of cranberries, blueberries, and thyme stretch out in back of the Victorian Maison Suisse House (144 Main St., Northeast Harbor, 207/276-5223, www.maisonsuisse.com , $175–395), which was named by a former owner from Switzerland. Located in Northeast Harbor village, the shingle-style summer cottage has fireplaces in the common rooms and tasteful, individually decorated guest rooms. Breakfast, either sit-down or take-out, is included from the restaurant/bakery across the street.
The grande dame of Bar Harbor  is unquestionably the Bar Harbor Inn (Newport Dr., Bar Harbor, 207/288-3351 or 800/248-3351, www.barharborinn.com , $200–380), a grand resort hotel overlooking the waterfront. The main building was once the social club for Victorian-era vacationers, and features the requisite Queen Anne turrets and curving circular dining room. The inn has been expanded with a three-story row of rooms overlooking the water, which are luxuriously appointed, if a bit cookie-cutter in style.