Alejandro Velasco Astete International Airport, Cusco: There is no airport at Ollantaytambo. Skip the expensive prebooked “airport transfer” unless you are a group: take a short taxi from CUZ to Cusco’s Pavitos/nearby colectivo departure area (roughly S/5–8), then a shared minibus or colectivo to Ollantaytambo (S/10–15; about 1½–2 hours once moving). Budget around 2–2½ hours door to door, longer in traffic. A private car is faster only if it leaves immediately and you can split the cost.
Cusco — Pavitos / Avenida Grau shared-van departures: This is the useful overland gateway from Cusco, not a formal bus terminal experience. Shared minibuses run through the day from Pavitos for about S/10; shared taxis are around S/15. Direct buses from Av. Grau have also operated for about S/5 at limited afternoon times, while the Urubamba connection is cheaper but slower: roughly S/1.50 to Urubamba plus S/3–6 onward. Take the direct minivan unless saving a few soles matters more than your time.
Ollantaytambo railway station: The station is for tourist trains between the Sacred Valley/Aguas Calientes route, chiefly PeruRail services; the local train is for residents and is monitored, so do not try to board it. The station is only about 400 m from Plaza de Armas—a 5–10 minute walk with luggage, not a taxi ride. If arriving from Machu Picchu, sleeping in Ollanta rather than rushing onward to Cusco is usually the sane choice.