Catch an early ferry from Dar es Salaam to Zanzibar costing about TZS 65,000 for economy class, giving you a scenic and affordable route to the island.
Free self-guided or affordable guided tours for around TZS 15,000 provide insight into the UNESCO World Heritage site's rich cultural history and architecture.
Take a boat to Prison Island for a small boat fee (~TZS 15,000) and low-cost admission (~TZS 5,000), where you can see giant tortoises and enjoy beaches cheaply.