Sendai has two subway lines that cover the main visitor areas: the Namboku Line runs north-south through the city centre, and the Tozai Line runs east-west. A day pass costs around 620 yen and covers both lines. The castle, Zuihoden, and Osaki Hachimangu are not on a subway line but are served by the Loople Sendai bus — a tourist circuit bus that runs every 20 minutes from the station and hits all the main sights on a one-way loop. A one-day pass costs 630 yen.
Taxis are plentiful and metered. The central sights are close enough that most visitors can walk between them once they've bused up to the hilltop area. Sendai is relatively flat in the downtown core, and the Jozenji-dori and Ichibancho covered arcade area is easily walkable.