Generally speaking, as you get closer the Ottawa River, the terrain will become flatter and there will thus be more farmland. This is also where the greatest concentration of people reside in the county. Although not synonymous the Ottawa Valley is closely associated with Renfrew County and the towns most closely associated with the valley (Arnprior, Renfrew and Pembroke) are all located in Renfrew country, on or near the river.
Renfrew Country is a region with one small city, Pembroke, and several medium sized towns and townships. The largest of these are Petawawa, Renfrew, and Arnprior. You may hear locals refer to Renfrew and Arnprior as "the Frew" or "the Prior". Numerous villages are present in Renfrew Country and often are linked to the nearby tourism.
The county confines are notable for the lack of any substantially sized park. This is for two reasons, the presence of Algonquin Park, which borders the county to much of the county's west, and the fact that the county comprises a part of cottage country (and forms a sort of transition area between cottage owners from Ottawa and Toronto.)
The region was first settled, as was most of North America, by First Nations people. In this region very few Native Americans still reside, though there is a presence near Golden Lake, including a pow wow once a year. As with many early attempts to penetrate the continents interior, the rivers served as the main route by which to do this and the Ottawa River was no exception. Later the river served as the conduit for the lumber trade, which made millionaires out of men in the region. The ties to the river are less strong these days, built still live on in some folklore, most notably Joseph Montferrand or Joe Muffaraw (depending on which side of the river you are on) a local strongman comparable to Paul Bunyan. Renfrew is considered by some to be the birthplace of the NHL, though there is little in the town to show for it.
There is a discernible accent in the Ottawa Valley though those that understand English will have little trouble understanding or being understood. There are some French speakers in the area as well, but even into the Quebec region on the other side of the Ottawa River English will be easily understood.
Despite the region's one time strong link to the railroad and the river, the only viable way to visit the region is by motor vehicle. Highway 60 from the west and highway 17 from the north and south form the main routes in the region. Bus service is possible to some areas, but there will often be only one bus per day.
Access to a motor vehicle is almost a necessity when traveling through the region, especially for areas off the beaten track. Greyhound services the major towns but at infrequent times. Some people take advantage of the relatively calm rivers to arrange multi day river journeys, but these also require some transport to and from.
The urban centers of Renfrew county serve primarily as local centers and have very few actual sites. These towns usually have a local museum, and in Renfrew and Arnprior the river offers a pleasant locale for a walk or picnic. For a more authentic experience head for the rural areas. Balaclava, not far from Renfrew, often makes the list for most picturesque villages in Ontario. Eganville is another village on the Bonnechere River (as is Renfrew) and has a nice setting. Nearby and also on the Bonnechere River are the Bonnechere Caves, a series of caves carved out of the limestone by the moving water. These are privately owned and there is an entrance fee involved. Wilno has strong ties to Polish culture, and those interested can find numerous Polish sites nearby. Foymount is the settlement in Ontario at the highest elevation. On County Road #9 north of Kelly's Corner stands a small piece of virgin forest.
There are no set itineraries for the region, as points of note are often tied to scenery as opposed to "must see" sites. One of the best ways to see the region is to explore the backroads. If you are driving between two points, check your map or inquire locally if there is a back way to go. Also be aware that some areas around Mount St. Patrick have uranium deposits and these areas are off limits and sometimes patrolled.
Food is limited to what is standard in rural Canada. Every town will have a greasy spoon, a Chinese restaurant, a fancier restaurant, a pizza place, and one or two fast food places.
If you ask around among locals you may be able to find some less common meats, which often come from hunting. Be aware that it is is also possible to buy illegal meat in this way, which is could result in some legal action. Outside of that things to look out for in summertime are church picnics or bbqs. Also the town of Wilno is known for its Polish fare.
Local taverns abound throughout the region, many of which amount to little more than watering holes, although several of these are where you'll be able to see some of the local culture of the region. Bars known for hosting live country and rock music are:
There are no specific safety precautions which should be taken. There is wildlife throughout the region, many of which are "scary" apex predators such as wolves and bears, but these animals have been vilified in the media, and in actuality account for very few attacks on humans (note this is the local black bear, not the more dangerous brown bear which is being referred to.) Other than that exercise caution only for cold in winter, and annoyances like poison ivy and biting insects in summer.
The Pontiac region of Quebec is similar to Renfrew county as it forms the other half of the Ottawa Valley.