Getting Around Colombo: Tuk-Tuks, PickMe, Trains and Buses
Colombo is bigger than it looks on a map and hotter than it looks on a forecast, which means you will use transport far more than you expect. The city has no metro, its bus network is impenetrable to newcomers, and its traffic is genuinely bad during peak hours. What it does have is an enormous supply of tuk-tuks, two working ride-hailing apps, and a coastal railway line that is one of the better bargains in Asian travel.
The single most useful thing to know before you arrive is that Colombo's tuk-tuks are supposed to be metered, and many are, but the ones waiting outside hotels and tourist sites will usually try a fixed price several times the meter fare. That is the entire negotiation, and there is a simple way around it. The second most useful thing is that PickMe, the local ride-hailing app, removes the negotiation altogether by pricing the trip before you get in.
Beyond that, distances within the tourist core are shorter than they feel. Fort to Pettah is a walk. Fort to Galle Face is a walk in cool weather. Galle Face to Gangaramaya is a very short ride. It is only when you head out to Cinnamon Gardens, Mount Lavinia or the airport that you are covering real ground.

Colombo City Sightseeing by Tuk-Tuk with Hotel Pickup
Bookable directly through AsiaByLocals, with a verified local operator.
From USD 52
3 hours