Getting to Rock Island requires two separate ferry rides, and once you arrive, you won’t find a single car, bike, or paved road anywhere on the 912-acre island. This is Wisconsin’s most unusual state park precisely because of what it lacks: no vehicles have ever been permitted here, making it a genuinely rare experience among Midwest state parks. Between the two-ferry logistics, cash-only transactions, and a seasonal window that closes for half the year, this island off the tip of the Door County peninsula rewards visitors who plan carefully.
Here’s what to know about the ferry system, camping, and current logistics before your 2026 trip.
Rock Island State Park Overview
| Detail | Information |
| Location | Northeast of Washington Island, Lake Michigan, Door County, WI |
| Park size | 912 acres |
| Vehicles | None permitted — no cars, no bikes on the island |
| Park hours | 6 a.m. to 11 p.m., year-round |
| Ferry season | Memorial Day weekend through the second Monday in October |
| Access route | Northport → Washington Island Ferry → drive across island → Rock Island Ferry (Karfi) |
| Trail mileage | About 10 miles, plus 6 miles of shoreline |
| Camping | 40 primitive walk-in tent sites, plus 2 group sites |
| Firewood | $5.50 per rick, cash only |
| Payment | Cash required for on-island purchases; credit cards not accepted aboard the Karfi ferry |
The Two-Ferry Journey: Plan Every Leg
This is genuinely the most important logistical detail for a Rock Island visit. Reaching the park requires two entirely separate ferries. First, drive Wisconsin Highway 42 to its end at Northport and take the Washington Island Ferry, which carries vehicles, bicycles, people, and freight across to Washington Island. From the Washington Island ferry landing, drive across the island via County Road W, roughly 8.4 miles and about 20 minutes, to Jackson Harbor on the island’s northeast side.
At Jackson Harbor, you’ll leave your vehicle and bike behind entirely, since neither is permitted on Rock Island, and board the passenger-only Rock Island Ferry, known as the Karfi, for the final short crossing. Fees apply for both ferry legs, and while the Washington Island Ferry ticket can be purchased at the Northport Pier ticket booth in advance, the Karfi accepts cash only on board, credit cards are not an option once you’re actually boarding for the second leg. Bring enough cash for your full round trip, since running short mid-visit has stranded more than one visitor forced to find an ATM back on Washington Island.
Seasonal Access: The Ferry Doesn’t Run Year-Round
While the park itself technically stays open year-round from 6 a.m. to 11 p.m., the Karfi ferry that actually gets you to Rock Island operates only from Memorial Day weekend through the second Monday in October. Outside this window, reaching the island by ferry simply isn’t possible, so plan your visit within this roughly four-and-a-half-month season. The ferry runs on a limited daily schedule with a handful of set departure times, so check the current schedule before you go and arrive with buffer time, since a missed departure can mean a long wait for the next one or an unplanned overnight.
Cash, Carts, and What You Can Actually Bring
Given the cash-only nature of transactions here, both gift shops on the island (one at the boathouse, one near the lighthouse) only accept cash, so budget accordingly for any souvenirs or supplies you might want to pick up on-site. Regarding gear, official guidance varies slightly by source: some park information notes that all camping supplies and equipment must be backpacked in without carts, while other current guidance indicates small carts are permitted both on the ferry and on the island, space and fees permitting. Given this ambiguity, plan to backpack your gear as the safer default, and treat any cart option as a bonus rather than a guarantee, since ferry space is limited and the captain has final say on what’s allowed aboard.
Camping: Primitive, Reservation-Only, and Cash for Firewood
Rock Island offers 40 primitive walk-in tent campsites plus two group campsites, each equipped with a picnic table and fire ring. Facilities are genuinely basic: pit or vault toilets, and drinking water available near the dock and boathouse, but nothing resembling a developed campground. All campsites must be reserved through the Wisconsin DNR reservation system before your trip, and all campers need to register at the visitor contact station upon arrival regardless of prior booking.
If you want a campfire, firewood is available for purchase on the island at $5.50 per rick, cash only, a detail worth remembering alongside your ferry fare cash when planning how much to bring.
Fishing and Paddling: Real Hazards Worth Knowing
Fishing at Rock Island requires a standard Wisconsin fishing license, and since no live bait is sold on the island, bring your own or plan to use artificial lures exclusively. Smallmouth bass and gobies are the most commonly caught species, with bass season opening July 1 in the surrounding waters.
For paddlers, canoes and kayaks are popular around the island, but Lake Michigan’s conditions can shift rapidly and dangerously, with wind and waves capable of turning a calm paddle into a genuine hazard with little warning. Early season conditions, specifically May and June, carry an additional hypothermia risk given how cold the water remains even as air temperatures warm. The Karfi ferry may transport canoes and kayaks for a small additional fee, though this is entirely at the captain’s discretion based on space and safety conditions that day, so don’t count on guaranteed passage for your watercraft.
History: Stone Buildings From a Wealthy Inventor’s Estate
Rock Island’s most distinctive built structures are the stone buildings constructed by Chester Thordarson, a wealthy inventor who owned the island from 1910 to 1945 and left behind architecture that now houses park exhibits. The Thordarson Loop Trail winds past several of these historic structures, and the roughly 1.3-mile hike from the boathouse to the Potawatomi Lighthouse remains one of the park’s most popular routes, delivering both historical interest and a genuine payoff view once you reach the bluff.
Frequently Asked Questions
Q1. Can I bring my car or bike onto Rock Island itself?
No. Vehicles and bicycles are prohibited entirely on Rock Island. You’ll leave both at Jackson Harbor on Washington Island before boarding the passenger-only Karfi ferry for the final crossing.
Q2. Does the Karfi ferry accept credit cards?
No, only cash is accepted aboard the Rock Island Ferry itself. The Washington Island Ferry ticket can be purchased with a card at the Northport Pier ticket booth beforehand, but budget cash specifically for the Rock Island leg and any on-island purchases.
Q3. Can I visit Rock Island in winter?
Not by ferry. While the park technically remains open year-round, the Karfi ferry that provides access only operates from Memorial Day weekend through the second Monday in October. Outside that window, reaching the island isn’t practically possible for most visitors.
Q4. Is it safe to kayak or canoe out to Rock Island on my own?
It’s possible, but Lake Michigan conditions can change quickly and dangerously, with real hypothermia risk from cold water especially in May and June. If you’re not an experienced open-water paddler familiar with the area’s reefs and weather patterns, taking the ferry is the considerably safer option.
