Gyumri is the second largest city in Armenia and the capital of Shirak Province in Northern Armenia. Much of the historic center dates to the days when Gyumri was an outpost of the Russian Czar in the Southern Caucasus, and the architecture reflects that. The buildings, of dark black stone are primarily 1800s Russian in style, with Armenian touches. Much of the center was destroyed by the 1988 quake which devastated the region, part of which has been rebuilt. There are also Russian churches, cemeteries and a large Russian base still dominates a part of the city.
Vans called marshrutki depart Yerevan for Gyumri from Kino Rosia's parking lot, above Zoravor Andranik subway station across from the National Cathedral. These are cheap, at about $5, but often crowded or uncomfortable. They are, however a great way to meet locals. Shared taxis depart from the same location and are usually faster and more comfortable. Taxis can be taken from anywhere in Yerevan or, indeed Armenia.
Another good option for a visit to Gyumri is a day tour from Yerevan. Many companies offer these, for a reasonable price, and allow you to get in a van, with other travelers and a guide, with stops along the way in places like Talin Cathedral and Harijavank Monastery. This is probably the easiest option, and may even work out to be your cheapest compared to taxis.
Gyumri's historic town center is quite walkable, and fun to explore, but beyond that it is a bit of a sprawling town, and to see everything it has to offer in a day, a car is needed. If you haven't come with your own, a taxi in town, with a meter, is probably your only realistic option, and a pretty good one at that. If you care to try and figure out the numbers of the local van routes (marshutni), you can have quite an adventure. It may be hard to make it to some of the fringe sites though in a marshutni, like the fortress.
Walk around the center, visit nearby monasteries (about 15km away to the closest), Visit museums (Hovhannes Shiraz, Avetik Issahakyan, Mher Mkrtchyan, Dzitoxtsonts Tun)travel to Georgia.
Off the main square, by the smaller black church, there is a diagonal pedestrian avenue with some shops and some outdoor vendors.
All restaurants close during holidays without notice. Proceed with caution if visiting around New Years or Christmas.
Lots of food stands and stalls on main pedestrian street.
Georgian marshrutkas leave every morning to Tbilisi and to Akhaltsikhe. There are marshrutkas that leave to Akhalkalaki and Akhaltsikhe in Georgia in the morning (10:00, to Akhaltsikhe 4000 AMD, arriving there around 14:00) and at 14:30 to Akhalkalaki (2000 AMD). If you arrive to the bus station after the morning marshrutkas leave but before 14:30 (for example, if you are coming from Dilijan), do not believe the taxi drivers that try to tell you that there will be no more marshrutkas to Akhalkalaki (in order to get you to ride with them for a high price). Many taxi drivers collude with the marshrutka drivers not to divulge the schedule to tourists to funnel them into high priced taxis. Your best strategy is to ask about the schedule in a store or restaurant nearby, or from your hotel/guesthouse.
Harich/Harihc is about 15km southeast up a mountain. It is a spectacular setting, and the church is very well preserved.