While cellular data coverage is quite good nowadays, there are still areas where the network coverage is weak. This is the case if you are in a middle of a forest in one of the many cottages in Finland. Fortunately, the solution can be pretty easy.
You can buy a 3G antenna like the 14dB GSM 900MHz and place it on the top of the roof, like the picture below. The direction of the antenna is important, before you place it permanently, try different directions.
Additionally, you need a 3G router with WiFi, for example the TP-Link TL-MR3220. You will also need a compatible 3G dongle with a SIM card, for example the Huawei E353. The antenna and the dongle are connected with a provided SMA connector.
In Finland, a 6 months prepaid SIM data card with 10GB of traffic costs just 25 euros. Configure the modem and then, you will enjoy WiFi coverage even in a middle of a Finnish forest 🙂