“Travel through primary rainforest to reach the end of a lava flow from the eruption of Volcan Arenal.
— David McCormick
Birding · Views · Wildlife
This loop will take you through the highlights of the Reserva Mirador el Silencio, starting in mature tertiary rainforest, scrambling over lava rocks from a recent volcanic explosion (1968), and then returning through rainforest.
Need to Know
This run is best completed early in the morning (ideally before 9AM) to avoid midday heat, drenching afternoon showers, and to maximize your chances of seeing wildlife. Move slowly and quietly through the rainforest – it is, after all, the "silent reserve."
After you reach the end of the first trail segment and the upper parking lot, be sure to close the gate behind you when headed to the lava flow so you don't let the cattle out!
This is not suitable for trail running.
Starting from the parking lot, head toward "Sendero Tabacon #3". You'll quickly enter dense, tertiary rainforest with large tropical hardwoods and a dense understory. The trail follows along a small stream with sturdy bridge crossings. During the rainy season (October-April), the trail can be very muddy, so bring sturdy shoes and a sense of adventure. Monkeys are most commonly seen in this section of the forest.
The trail will then turn southeast and begin to slope steadily uphill. Switchbacks are rare and some scrambling is needed if the trail is too muddy. The trail then leaves the tertiary forest and you are greeted with an exceptional view of Volcan Arenal, a nearby lake, and cleared fields. Toucans and raptors are common in this valley along treetops – listen for their calls.
From here, the trail then moves northeast, hugging the edge of the forest. You'll cross the pasture/valley and come to a large upper parking lot, where there is a sign leading to Sendero Lava del 68 - Lava Flow 1968
. Go through the cattle gate and run for ~0.1 miles along level pasture before reaching a dense forest. Make your way through this along the trail, scrambling up lava rocks and boulders. The trail then makes a sharp southerly turn, following a ridgeline with, you guessed it, more lava rocks.
The end of the trail is not clearly marked, so use caution. Lava rocks are sharp, so taking a tumble here would be painful. The view at the end of this trail is outstanding – you'll have a better view of the lake, you can stare right up at the volcano cone, and you can see back to a green lake to the north about 500 feet below.
When you've had your fill of the amazing view, head back down the lava flow and return to the upper parking lot, where you should pick up the Sendero Los Araña
. This trail will take you through more tertiary rainforest with multiple large Ceiba trees and more chances to spot jungle wildlife. This section is steep in parts and without switchbacks, so use caution after a rain or during the rainy season. The trail will then end at the lower parking lot where you started.
Flora & Fauna
Fauna are abundant along this trail. Move slowly and keep a close eye on the forest, ground, and sky. Early in the morning, howler monkeys may be seen swinging through the trees, leaf cutter ants often cross the trail, and coati are ubiquitous. Snakes are a concern, as elsewhere in the rainforest, so look carefully before grabbing vines or reaching out to plants. There are many different bird species, including parrots and toucans. Listen for their calls. Flora include dense secondary and tertiary rainforest, Ceiba trees, and other tropical hardwoods.
History & Background
Volcan Arenal looms over the reserve. It was thought to be dormant until 1968, when it exploded violently, sending towering ash plumes into the air and cascading lava flows and pyroclastic flows down the sides. Needless to say, much of the rainforest in this area was destroyed, but has since rebounded quite well. The volcano remains active and can be seen smoking most clear afternoons.