diff --git a/challenges/2021/01-sonarSweep/benchmark.txt b/challenges/2021/01-sonarSweep/benchmark.txt
new file mode 100644
index 0000000..8409240
--- /dev/null
+++ b/challenges/2021/01-sonarSweep/benchmark.txt
@@ -0,0 +1,23 @@
+Day 1 (Sonar Sweep) benchmark
+
+Dir: challenges/2021/01-sonarSweep
+Runs per part: 200
+--------------------------------------------------------------------------------
+Golang
+
+benchmark.part.1.avg: 0.000094 seconds
+benchmark.part.1.min: 0.000047 seconds
+benchmark.part.1.max: 0.000818 seconds
+benchmark.part.2.avg: 0.000112 seconds
+benchmark.part.2.min: 0.000057 seconds
+benchmark.part.2.max: 0.000535 seconds
+--------------------------------------------------------------------------------
+Python
+
+benchmark.part.1.avg: 0.001437 seconds
+benchmark.part.1.min: 0.000452 seconds
+benchmark.part.1.max: 0.012373 seconds
+benchmark.part.2.avg: 0.002187 seconds
+benchmark.part.2.min: 0.000762 seconds
+benchmark.part.2.max: 0.005535 seconds
+--------------------------------------------------------------------------------
diff --git a/challenges/2021/01-sonarSweep/go/challenge.go b/challenges/2021/01-sonarSweep/go/challenge.go
new file mode 100644
index 0000000..2698e1b
--- /dev/null
+++ b/challenges/2021/01-sonarSweep/go/challenge.go
@@ -0,0 +1,62 @@
+package challenge
+
+import (
+	"strconv"
+	"strings"
+
+	"github.com/codemicro/adventOfCode/lib/aocgo"
+)
+
+func parse(instr string) ([]int, error) {
+	var o []int
+	for _, line := range strings.Split(instr, "\n") {
+		if line == "" {
+			continue
+		}
+		t := strings.TrimSpace(line)
+		n, err := strconv.Atoi(t)
+		if err != nil {
+			return nil, err
+		}
+		o = append(o, n)
+	}
+	return o, nil
+}
+
+func countIncreases(data []int) int {
+	var c int
+	for i := 1; i < len(data); i += 1 {
+		if data[i] > data[i-1] {
+			c += 1
+		}
+	}
+	return c
+}
+
+type Challenge struct {
+	aocgo.BaseChallenge
+}
+
+func (c Challenge) One(instr string) (interface{}, error) {
+	data, err := parse(instr)
+	if err != nil {
+		return nil, err
+	}
+	return countIncreases(data), nil
+}
+
+func (c Challenge) Two(instr string) (interface{}, error) {
+	data, err := parse(instr)
+	if err != nil {
+		return nil, err
+	}
+
+	var sums []int
+	{
+		for i := 0; i < len(data)-2; i += 1 {
+			sums = append(sums, data[i]+data[i+1]+data[i+2])
+		}
+	}
+
+	return countIncreases(sums), nil
+}