Getting to Álamos
Álamos sits up in the foothills about 50 km southeast of Navojoa, and there is no airport and no big long-distance bus terminal in town. However you come, you route through Navojoa first and cover the last stretch into the hills from there.
By air
The nearest useful airport is Ciudad Obregón (CEN), roughly an hour and a bit north of Navojoa by road. A bit farther but often better connected is Los Mochis (LMM) down in Sinaloa, around a couple of hours south. Hermosillo (HMO) is the biggest airport in the state with the most flights, but it is a longer haul, four hours or so up the highway (approximate). From any of them you drive or bus to Navojoa, then do the final hour on to Álamos. Reckon roughly an hour from Ciudad Obregón to Navojoa plus about another hour up to Álamos, and pad it.
By bus
Long-distance buses run to Navojoa from all over the northwest along the Highway 15 corridor. TAP and Tufesa are the main operators you will see linking Hermosillo, Ciudad Obregón, Los Mochis and points beyond, and the bigger lines running the Pacific route call here too. From Hermosillo to Navojoa is roughly 4 to 5 hours and something like 400 to 600 MXN (approximate); from Los Mochis it is shorter. From the Navojoa terminal, local buses and colectivos make the roughly hour-long run out to Álamos through the foothills for a small fare. It is doable without a car but slower and less flexible, and the last connection back to Navojoa can be earlier than you would like, so check return times before you commit to arriving late or day-tripping out.
By car
Driving is the easy option and the one most winter visitors take. Highway 15 runs the length of the state to Navojoa, then a paved, well-signed road climbs the last hour east into the hills to Álamos. The climb is scenic and straightforward in daylight. Do it in daylight, though: the road is unlit, rural stretches have no shoulder, and livestock on the road at night is a real thing here. Fill up in Navojoa, because fuel and services thin out once you leave the highway.
Getting around town
Once you arrive, park the car and walk. Álamos is small, mostly flat and entirely walkable, you can cross the historic core in about twenty minutes, and there is genuinely nowhere in town you need a vehicle to reach. There is no colectivo network worth using inside town and no ride-hail apps up here; the handful of local taxis are hailed on the plaza or arranged through your hotel, and you agree the fare before you get in.
The one real caution is underfoot and after dark. The streets are cobblestone and uneven, and lighting is patchy the moment you leave the plaza, so bring decent shoes and a small flashlight for walking back from dinner. For trips out to La Aduana, the Cuchujaqui river or the birding arroyos, you will want your own vehicle or, better, a hired guide with one who actually knows the rough roads.