The centre is small enough to walk — Hayk Square, the museum, the church, the theatre, and the better cafes are all within a fifteen-minute radius. Local marshrutkas serve the outer neighbourhoods and cost a few hundred dram. Taxis are cheap and easy to flag down or order via the GG app; insist on the meter or settle the price before getting in.
For day trips into Lori province, hiring a taxi for the day is straightforward and usually negotiable down to a sensible rate if you ask at your guesthouse. Public marshrutkas reach the larger villages but run on their own schedules and dry up by early afternoon.