"Free" walking tours
Widely available in the Old Town, these general-introduction tours run on a tip-what-you-think-it's-worth basis, typically covering the Old Town Square, Charles Bridge and a bit of history in two to three hours. They're a genuinely good way to get oriented on day one, especially with a guide who clearly knows the material — but quality varies a lot between guides, so it's worth checking recent reviews for the specific company and time slot, not just the tour brand.
Food tours
A guided food tour is one of the better ways to get past the tourist-menu version of Czech food covered in our food & drink guide — a good guide will take you to places you wouldn't find or wouldn't feel confident ordering at alone, and explain what you're eating as you go.
Specialist tours
Prague's 20th-century history — occupation, communism, the Velvet Revolution — is dense enough that a specialist guide adds real value over a plaque and a guidebook paragraph, especially around Wenceslas Square. The Jewish Quarter is another place where a knowledgeable guide changes the experience meaningfully, given how much of what you're looking at is memorial rather than simply historic.
When to skip the guide
For the core physical sights — Charles Bridge, the castle grounds, the river walk — a good self-guided route (see our 3-day itinerary) covers the ground perfectly well without a group pace to keep up with. Save the guided budget for the places where local knowledge genuinely unlocks something: food, and the harder 20th-century history.