diff --git a/crates/cast/bin/cmd/run.rs b/crates/cast/bin/cmd/run.rs
index 11c7b507e355..7389d1f35e4d 100644
--- a/crates/cast/bin/cmd/run.rs
+++ b/crates/cast/bin/cmd/run.rs
@@ -5,7 +5,7 @@ use cast::revm::primitives::EnvWithHandlerCfg;
 use clap::Parser;
 use eyre::{Result, WrapErr};
 use foundry_cli::{
-    opts::RpcOpts,
+    opts::{EtherscanOpts, RpcOpts},
     utils::{handle_traces, init_progress, TraceResult},
 };
 use foundry_common::{is_known_system_sender, SYSTEM_TRANSACTION_TYPE};
@@ -58,13 +58,16 @@ pub struct RunArgs {
     #[arg(long, short)]
     label: Vec<String>,
 
+    #[command(flatten)]
+    etherscan: EtherscanOpts,
+
     #[command(flatten)]
     rpc: RpcOpts,
 
     /// The EVM version to use.
     ///
     /// Overrides the version specified in the config.
-    #[arg(long, short)]
+    #[arg(long)]
     evm_version: Option<EvmVersion>,
 
     /// Sets the number of assumed available compute units per second for this provider
@@ -269,6 +272,10 @@ impl figment::Provider for RunArgs {
             map.insert("alphanet".into(), self.alphanet.into());
         }
 
+        if let Some(api_key) = &self.etherscan.key {
+            map.insert("etherscan_api_key".into(), api_key.as_str().into());
+        }
+
         if let Some(evm_version) = self.evm_version {
             map.insert("evm_version".into(), figment::value::Value::serialize(evm_version)?);
         }
diff --git a/crates/cast/tests/cli/main.rs b/crates/cast/tests/cli/main.rs
index 6fb3ddb73c58..29527f7dc3bb 100644
--- a/crates/cast/tests/cli/main.rs
+++ b/crates/cast/tests/cli/main.rs
@@ -6,8 +6,8 @@ use anvil::{EthereumHardfork, NodeConfig};
 use foundry_test_utils::{
     casttest, file,
     rpc::{
-        next_http_rpc_endpoint, next_mainnet_etherscan_api_key, next_rpc_endpoint,
-        next_ws_rpc_endpoint,
+        next_etherscan_api_key, next_http_rpc_endpoint, next_mainnet_etherscan_api_key,
+        next_rpc_endpoint, next_ws_rpc_endpoint,
     },
     str,
     util::OutputExt,
@@ -1503,3 +1503,28 @@ casttest!(fetch_constructor_args_from_etherscan, |_prj, cmd| {
 
 "#]]);
 });
+
+// <https://github.com/foundry-rs/foundry/issues/3473>
+casttest!(test_non_mainnet_traces, |prj, cmd| {
+    prj.clear();
+    cmd.args([
+        "run",
+        "0xa003e419e2d7502269eb5eda56947b580120e00abfd5b5460d08f8af44a0c24f",
+        "--rpc-url",
+        next_rpc_endpoint(NamedChain::Optimism).as_str(),
+        "--etherscan-api-key",
+        next_etherscan_api_key(NamedChain::Optimism).as_str(),
+    ])
+    .assert_success()
+    .stdout_eq(str![[r#"
+Executing previous transactions from the block.
+Traces:
+  [33841] FiatTokenProxy::fallback(0x111111125421cA6dc452d289314280a0f8842A65, 164054805 [1.64e8])
+    ├─ [26673] FiatTokenV2_2::approve(0x111111125421cA6dc452d289314280a0f8842A65, 164054805 [1.64e8]) [delegatecall]
+    │   ├─ emit Approval(owner: 0x9a95Af47C51562acfb2107F44d7967DF253197df, spender: 0x111111125421cA6dc452d289314280a0f8842A65, value: 164054805 [1.64e8])
+    │   └─ ← [Return] true
+    └─ ← [Return] true
+...
+
+"#]]);
+});
diff --git a/crates/evm/core/src/opts.rs b/crates/evm/core/src/opts.rs
index 7a41d075641b..17ecbcca170e 100644
--- a/crates/evm/core/src/opts.rs
+++ b/crates/evm/core/src/opts.rs
@@ -192,10 +192,6 @@ impl EvmOpts {
     /// Returns the chain ID from the RPC, if any.
     pub async fn get_remote_chain_id(&self) -> Option<Chain> {
         if let Some(ref url) = self.fork_url {
-            if url.contains("mainnet") {
-                trace!(?url, "auto detected mainnet chain");
-                return Some(Chain::mainnet());
-            }
             trace!(?url, "retrieving chain via eth_chainId");
             let provider = ProviderBuilder::new(url.as_str())
                 .compute_units_per_second(self.get_compute_units_per_second())
@@ -206,6 +202,14 @@ impl EvmOpts {
             if let Ok(id) = provider.get_chain_id().await {
                 return Some(Chain::from(id));
             }
+
+            // Provider URLs could be of the format `{CHAIN_IDENTIFIER}-mainnet`
+            // (e.g. Alchemy `opt-mainnet`, `arb-mainnet`), fallback to this method only
+            // if we're not able to retrieve chain id from `RetryProvider`.
+            if url.contains("mainnet") {
+                trace!(?url, "auto detected mainnet chain");
+                return Some(Chain::mainnet());
+            }
         }
 
         None
diff --git a/crates/test-utils/src/rpc.rs b/crates/test-utils/src/rpc.rs
index 7f0742143e4c..a974e395406d 100644
--- a/crates/test-utils/src/rpc.rs
+++ b/crates/test-utils/src/rpc.rs
@@ -1,6 +1,6 @@
 //! RPC API keys utilities.
 
-use foundry_config::NamedChain;
+use foundry_config::{NamedChain, NamedChain::Optimism};
 use rand::seq::SliceRandom;
 use std::sync::{
     atomic::{AtomicUsize, Ordering},
@@ -75,6 +75,10 @@ static ETHERSCAN_MAINNET_KEYS: LazyLock<Vec<&'static str>> = LazyLock::new(|| {
     keys
 });
 
+// List of etherscan keys for Optimism.
+static ETHERSCAN_OPTIMISM_KEYS: LazyLock<Vec<&'static str>> =
+    LazyLock::new(|| vec!["JQNGFHINKS1W7Y5FRXU4SPBYF43J3NYK46"]);
+
 /// Returns the next index to use.
 fn next() -> usize {
     static NEXT_INDEX: AtomicUsize = AtomicUsize::new(0);
@@ -127,6 +131,16 @@ pub fn next_mainnet_etherscan_api_key() -> String {
     ETHERSCAN_MAINNET_KEYS[idx].to_string()
 }
 
+/// Returns the next etherscan api key for given chain.
+pub fn next_etherscan_api_key(chain: NamedChain) -> String {
+    let keys = match chain {
+        Optimism => &ETHERSCAN_OPTIMISM_KEYS,
+        _ => &ETHERSCAN_MAINNET_KEYS,
+    };
+    let idx = next() % keys.len();
+    keys[idx].to_string()
+}
+
 fn next_url(is_ws: bool, chain: NamedChain) -> String {
     use NamedChain::*;