Northern Armenia includes the 3 northernmost provinces of Armenia. The western part of this region is arid, while the central and eastern parts are often lush and green, with much of Armenia's forests. The Debed river canyon of Lori Province is particularly beautiful and rich in monuments, along with the rolling hills of the remote Shamshadin, centered around Berd, and Dilijan-Ijevan.
Northern Armenia, as defined here, includes Shirak, Lori and Tavush Marzes.
Lori and Tavush are some of the greenest parts of Armenia, with a lot of forests along bordering regions especially. The northernmost part of Lori had its history intertwined with Georgia's for many centuries. The north and northeast are also extremely rich in monasteries and other historic monuments. Days can be spent visiting and hiking to them. The whole area is great for hikers, with no fences, and lots of back country trails. Camping is acceptable just about anywhere.
Gyumri was devastated by an earthquake in 1988 and so was Spitak. Recovery was excruciatingly slow, but now things are for the most part restored - at least to levels of normalcy seen in other parts of Armenia. You will, however still notice earthquake damage in Gyumri.
Armenian is universally spoken and Russian nearly so. English, French and German are less so, but English proficiency is growing rapidly.
Each of the three Marzes has a main highway from Yerevan. One goes to Gyumri, one to Vanadzor-Alaverdi-Georgia, and the third to Dilijan-Noyemberyan-Georgia (via Lake Sevan). Options to get out to each of these regions is day trips/tours, renting a car, taking a taxi, or public transportation. Gyumri, Vanadzor and Dilijan are all no more than 1½-2 hours from Yerevan, and a day trip is easy. If you want to go beyond these cities though, it can become harder to fit it all into a day trip, and looking into spending the night becomes worthwhile.
If you get to each of these cities by public transportation, you can negotiate with taxis for getting to the regional sites, though be prepared for tough negotiations. ֏100 per kilometer and US$3-5 an hour for waiting are standard taxi fares in Yerevan and certainly sufficient in the outlying regions.
In the Dilijan area there are some nicer restaurants, and riverside fish and traditional barbecue joints, while almost everywhere else you can find a roadside barbecue every so often. Gyumri and Vanadzor also have many choices for food. Bigger towns have open markets (shukas) where you can get some fresh fruits, bread and sandwich ingredients, and they may sell some prepared foods, khachapuris. shawerma and lahmejuns.
Gyumri has its own beer named after the town (also available in Yerevan). Much of Armenia's small rock scene originates in Gyumri and Vanadzor, where there are some bars and clubs.
The only real danger across this region is in the very northeast along the border with Azerbaijan. If you get close to the border, they have been known to shoot into Armenia.
Aside from the numerous vans (marshutni) and buses headed towards Yerevan (Երեվան), which you can hop into, you can take a taxi, or if you're really adventurous and have too much time on your hands, take the train which goes Alaverdi-Vanadzor-Gyumri-Yerevan (and reverse to Tbilisi). You can also catch transport to Tbilisi from many towns in northwest and northcentral Armenia. From the northeast you can catch transport to Lake Sevan.